inside the atom

ions and isotopes

The number of protons per atom is always the same for a given element. However, the number of neutrons may vary, and the number of electrons can change.

ions

Sometimes atoms lose or gain electrons. Then they become ions. Ions have a positive or negative charge. Thats because they do not have the same number of electrons as protons. If atoms lose electrons, they become positive ions, or cations. If atoms gain electrons, they become negative ions, or anions. Consider the example of fluorine in Figure 5.5. A fluorine atom has nine protons and nine electrons, so it is electrically neutral. If a fluorine atom gains an electron, it becomes a fluoride ion with a negative charge of minus one.

textbook_image

isotopes of atoms

Some atoms of the same element may have different numbers of neutrons. For example, some carbon atoms have seven or eight neutrons instead of the usual six. Atoms of the same element that differ in number of neutrons are called isotopes. Many isotopes occur naturally. Usually one or two isotopes of an element are the most stable and common. Different isotopes of an element generally have the same chemical properties. Thats because they have the same numbers of protons and electrons. For a video explanation of isotopes, go to this URL: MEDIA Click image to the left or use the URL below. URL:

an example hydrogen isotopes

Hydrogen is a good example of isotopes because it has the simplest atoms. Three isotopes of hydrogen are modeled in Figure 5.6. Most hydrogen atoms have just one proton and one electron and lack a neutron. They are just called hydrogen. Some hydrogen atoms have one neutron. These atoms are the isotope named deuterium. Other hydrogen atoms have two neutrons. These atoms are the isotope named tritium.

naming isotopes

For most other elements, isotopes are named for their mass number. For example, carbon atoms with the usual 6 neutrons have a mass number of 12 (6 protons + 6 neutrons = 12), so they are called carbon-12. Carbon atoms with 7 neutrons have an atomic mass of 13 (6 protons + 7 neutrons = 13). These atoms are the isotope called carbon-13. Some carbon atoms have 8 neutrons. What is the name of this isotope of carbon? You can learn more about this isotope at the URL below. It is used by scientists to estimate the ages of rocks and fossils.

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back to quarks

Remember the quarks from the first page of this chapter? Quarks are even tinier particles of matter that make up protons and neutrons. There are three quarks in each proton and three quarks in each neutron. The charges of quarks are balanced exactly right to give a positive charge to a proton and a neutral charge to a neutron. It might seem strange that quarks are never found alone but only as components of other particles. This is because the quarks are held together by very strange particles called gluons.

atomic number and mass number

Electrons have almost no mass. Instead, almost all the mass of an atom is in its protons and neutrons in the nucleus. The nucleus is very small, but it is densely packed with matter. The SI unit for the mass of an atom is the atomic mass unit (amu). One atomic mass unit equals the mass of a proton, which is about 1.7 10 24 g. Each neutron also has a mass of 1 amu. Therefore, the sum of the protons and neutrons in an atom is about equal to the atoms total mass in atomic mass units. Two numbers are commonly used to distinguish atoms: atomic number and mass number. Figure 5.4 shows how these numbers are usually written. The atomic number is the number of protons in an atom. This number is unique for atoms of each kind of element. For example, the atomic number of all helium atoms is 2. The mass number is the number of protons plus the number of neutrons in an atom. For example, most atoms of helium have 2 neutrons, so their mass number is 2 + 2 = 4. This mass number means that an atom of helium has a mass of about 4 amu. Problem Solving Problem: An atom has an atomic number of 12 and a mass number of 24. How many protons and neutrons does the atom have? Solution: The number of protons is the same as the atomic number, or 12. The number of neutrons is equal to the mass number minus the atomic number, or 24 12 = 12. You Try It! Problem: An atom has an atomic number of 8 and a mass number of 16. How many neutrons does it have? What is the atoms mass in atomic mass units?

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atomic forces

When it comes to atomic particles, opposites attract. Negative electrons are attracted to positive protons. This force of attraction keeps the electrons moving about the nucleus. An analogy is the way planets orbit the sun. What about particles with the same charge, such as protons in the nucleus? They push apart, or repel, each other. So why doesnt the nucleus fly apart? The reason is a force of attraction between protons and neutrons called the strong force. The name of the strong force suits it. It is stronger than the electric force pushing protons apart. However, the strong force affects only nearby particles (see Figure 5.3). It is not effective if the nucleus gets too big. This puts an upper limit on the number of protons an atom can have and remain stable. You can learn more about atomic forces in the colorful tutorial at this URL: .

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electrons

An electron is a particle outside the nucleus of an atom that has a negative electric charge. The charge of an electron is opposite but equal to the charge of a proton. Atoms have the same number of electrons as protons. As a result, the negative and positive charges "cancel out." This makes atoms electrically neutral. For example, a carbon atom has six electrons that "cancel out" its six protons.

textbook_image

neutrons

A neutron is a particle in the nucleus of an atom that has no electric charge. Atoms of an element often have the same number of neutrons as protons. For example, most carbon atoms have six neutrons as well as six protons. This is also shown in Figure 5.2.

protons

A proton is a particle in the nucleus of an atom that has a positive electric charge. All protons are identical. It is the number of protons that gives atoms of different elements their unique properties. Atoms of each type of element have a characteristic number of protons. For example, each atom of carbon has six protons, as you can see in Figure

the nucleus

At the center of an atom is the nucleus (plural, nuclei). The nucleus contains most of the atoms mass. However, in size, its just a tiny part of the atom. The model in Figure 5.1 is not to scale. If an atom were the size of a football stadium, the nucleus would be only about the size of a pea. The nucleus, in turn, consists of two types of particles, called protons and neutrons. These particles are tightly packed inside the nucleus. Constantly moving about the nucleus are other particles called electrons. You can see a video about all three types of atomic particles at this URL: (1:57).

parts of the atom

Figure 5.1 represents a simple model of an atom. You will learn about more complex models in later lessons, but this model is a good place to start. You can see similar, animated models of atoms at this URL: http://web.jjay.cuny

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gluons

Gluons make quarks attract each other more strongly the farther apart the quarks get. To understand how gluons work, imagine holding a rubber band between your fingers. If you try to move your hands apart, they will be pulled back together by the rubber band. The farther apart you move your hands, the stronger the force of the rubber band pulling your hands together. Gluons work the same way on quarks inside protons and neutrons (and other, really rare particles too). If you were to move your hands apart with enough force, the rubber band holding them together would break. The same is true of quarks. If they are given enough energy, they pull apart with enough force to "break" the binding from the gluons. However, all the energy that is put into a particle to make this possible is then used to create a new set of quarks and gluons. And so a new proton or neutron appears.

kqed homegrown particle accelerators

QUEST journeys back to find out how physicists on the UC Berkeley campus in the 1930s, and at the Stanford Linear Accelerator Center in the 1970s, created "atom smashers" that led to key discoveries about the tiny constituents of the atom and paved the way for the Large Hadron Collider in Switzerland. For more information on particle accelerators, see http://science.kqed.org/quest/video/homegrown-particle-accelerators/ . MEDIA Click image to the left or use the URL below. URL:

finding quarks

The existence of quarks was first proposed in the 1960s. Since then, scientists have done experiments to show that quarks really do exist. In fact, they have identified six different types of quarks. However, much remains to be learned about these tiny, fundamental particles of matter. They are very difficult and expensive to study. If you want to learn more about them, including how they are studied, the URL below is a good place to start.

instructional diagrams

description_image

This diagram shows the makings of an atom. The nucleus contains protons and neutrons, which are represented as green and orange spheres. Protons have positive charges and neutrons have no charge. The rings outside the nucleus contain electrons, which have negative charges. The electrons are represented by purple spheres. The atom's mass is made up of the protons and neutrons. The outermost ring of electrons is called the valence ring, which contains one valence electron in this diagram.

description_image

Carbon has three isotopes which are shown in this diagram. Carbon always has six protons, but the number of neutrons it has can vary. The number of positively charged protons in an isotope is called the atomic number. The mass number of an isotope is equal to the number of its positively charged protons plus the number it's of neutrally charged neutrons. A Carbon-12 atom has six protons and six neutrons in its nucleus. A Carbon-13 isotope has six protons and seven neutrons in its nucleus, giving it a mass number of thirteen. Tritium has a proton and two neutrons in its nucleus, giving it a mass number of three. All three have a single electron. Another isotope of carbon, Carbon-14 has six protons and eight neutrons in its nucleus, giving it a mass number of fourteen.

description_image

Three isotopes of hydrogen are shown here. The number of protons in an atom determines the element, but the number of neutrons the atom of an element has can vary. The number of positively charged protons in an isotope is called the atomic number. This will also equal the number of electrons in a neutrally charged atom. The mass number of an isotope is equal to its atomic number plus the number of neutrally charged neutrons it has. A hydrogen atom has one proton and zero neutrons in its nucleus. Hyrogen has two isotopes called deuterium and tritium. Deuterim has a proton and a neutron in its nucleus, giving it a mass number of two. Tritium has a proton and two neutrons in its nucleus, giving it a mass number of three. All three have a single electron.

description_image

The figure shows the nuclear symbol for the chemical element Boron. There are two important numbers in a nuclear symbol. In the lower left part, there is the atomic number. The atomic number shows the number of protons. In the upper left part, there is the mass number. The mass number is the sum of the number of protons and neutrons. In addition, if the element is an ion, the charge is shown in the upper right part of the symbol.

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The diagram shows how elements are written in relation to the mass and atomic number. The symbol X stands for the chemical symbol of the element. Two numbers are commonly used to distinguish atoms: atomic number and mass number. The symbol A at the top right of the element symbol refers to the mass number. Mass number is the number of protons plus the number of neutrons in an atom. The symbol Z at the bottom right of the element symbol refers to the atomic number. The atomic number is the number of protons in an atom. This number is unique for atoms of each kind of element.

description_image

The figure shows a diagrammatic representation of a Helium-4 atom. We see how the atom has a nucleus surrounded by shells of electrons. In this case, the atom has two protons and two neutrons in the central nucleus. Two electrons orbit around the nucleus. The electrons are both in the first shell. The protons have a positive charge. The electrons have a negative charge. The neutrons do not have a charge.

description_image

This diagram shows a simple model of an atom. At the center of the atom is the nucleus. The nucleus contains neutrons and protons. A proton is a particle with a positive electric charge. The neutron is a particle with no electric charge. Electrons are particles with negative charges. They revolve around the nucleus in orbits. An atom typically has the same number of protons and electrons. Hence the positive and negative charges cancel each other out.

description_image

This image shows the electron shells of a Germanium atom. There are a totals of 32 orbiting electrons in four distinct shells. The inner shell has two electrons. The second shell has 8 electrons. The third shell has 18 electrons. The fourth, outer shell has 4 electrons. The electrons in the outer shell are called valence electrons. In the center of the atom sits the nucleus. The nucleus has a positive charge.

questions

electrically neutral atomic particle inside the nucleus of an atom

a. electron

b. ion

c. isotope

-->  d. neutron

e. nucleus

f. proton

g. quark

The smallest particles of an element that still have the elements properties are

a. quarks.

b. gluons.

c. protons.

-->  d. atoms.

atom that differs in its number of neutrons from other atoms of the same element

a. electron

b. ion

-->  c. isotope

d. neutron

e. nucleus

f. proton

g. quark

Which statement is true about the nucleus of an atom?

a. It makes up most of the atoms volume.

-->  b. It makes up most of the atoms mass.

c. It contains protons and electrons.

d. It is neutral in electric charge.

negatively charged atomic particle that moves around the nucleus of an atom

-->  a. electron

b. ion

c. isotope

d. neutron

e. nucleus

f. proton

g. quark

The strong force explains why

a. electrons are attracted to the nucleus.

-->  b. the nucleus does not fly apart.

c. electrons are smaller than protons.

d. none of the above

The mass number of an atom is its number of

a. electrons.

b. protons.

c. neutrons.

-->  d. protons plus neutrons.

positively charged atomic particle inside the nucleus of an atom

a. electron

b. ion

c. isotope

d. neutron

e. nucleus

-->  f. proton

g. quark

type of particle that makes up protons and neutrons

a. electron

b. ion

c. isotope

d. neutron

e. nucleus

f. proton

-->  g. quark

When a fluorine atom gains an electron, it becomes a(n)

a. positive ion.

b. isotope.

c. cation.

-->  d. anion.

charged particle that forms when atom gains or loses electron(s)

a. electron

-->  b. ion

c. isotope

d. neutron

e. nucleus

f. proton

g. quark

tiny region at the center of an atom that contains protons and neutrons

a. electron

b. ion

c. isotope

d. neutron

-->  e. nucleus

f. proton

g. quark

All protons are exactly the same.

-->  a. true

b. false

Electrons have the same mass as protons.

a. true

-->  b. false

Atoms may be positive or negative in charge.

a. true

-->  b. false

All atoms of a given element have the same number of electrons.

-->  a. true

b. false

There are three quarks in each neutron.

-->  a. true

b. false

Atoms are the smallest particles of matter.

a. true

-->  b. false

An atom always has the same number of electrons as neutrons.

a. true

-->  b. false

The nucleus is at the center of the atom.

-->  a. true

b. false

Atoms have no electric charge.

-->  a. true

b. false

The strong force keeps electrons moving around the nucleus.

a. true

-->  b. false

Electrons have almost no mass.

-->  a. true

b. false

The mass of an atom equals the sum of its protons and neutrons.

-->  a. true

b. false

For most elements, isotopes are named for their atomic number.

a. true

-->  b. false

Each proton consists of three quarks.

-->  a. true

b. false

Quarks are held together by gluons.

-->  a. true

b. false

If an atom were the size of a football stadium, the nucleus would be about the size of a

a. microwave oven.

b. basketball.

-->  c. pea.

d. car.

The number of protons in atoms is

a. the same for all atoms.

-->  b. unique for each element.

c. always equal to the number of neutrons.

d. none of the above

The strong force

a. affects only nearby particles.

b. is stronger than electric force.

c. is not effective if the nucleus is too big.

-->  d. all of the above

A neutron has the same mass as a(n)

a. nucleus.

b. electron.

-->  c. proton.

d. quark.

A nitrogen atom has an atomic number of 7 and a mass number of 14. How many protons, neutrons, and electrons does it have?

a. 7 protons, 14 neutrons, 7 electrons

b. 14 protons, 7 neutrons, 7 electrons

-->  c. 7 protons, 7 neutrons, 7 electrons

d. 7 protons, 7 neutrons, 14 electrons

If an atom loses electrons, it becomes a(n)

a. isotope.

-->  b. cation.

c. anion.

d. gluon.

How many neutrons are there in the most common isotope of hydrogen?

-->  a. zero

b. one

c. two

d. three

diagram questions

question_image

How many protons are in an Aluminium atom?

a. 14

-->  b. 13

c. 27

d. 40

question_image

What does the atomic number indicate?

a. A total number of atoms

b. A total number of electrons

-->  c. A total number of protons

d. A total number of neutrons

question_image

What is the relative atomic mass of aluminum?

-->  a. 27

b. 13

c. 15

d. 20

question_image

What is the Mass Number of Mg?

-->  a. 27

b. 35

c. 17

d. 12

question_image

How many positively charged particles does Cl have?

a. 18

b. 34

-->  c. 17

d. 35

question_image

Identify the number commonly used to distinguish an atom

a. Protons Number

b. Neutrons Number

-->  c. Mass number

d. Electrons Number

question_image

What is the atomic number for Cl?

a. 35

b. 12

-->  c. 17

d. 27

question_image

How many neutrons does chlorine have?

a. 12

b. 35

c. 17

-->  d. 18

question_image

What is the atomic number of magnesium?

a. 17

b. 35

-->  c. 12

d. 27

question_image

What number in the diagram shows the atomic number?

a. e

b. H

c. 4

-->  d. 2

question_image

What is atomic number of the element Helium?

a. 4

b. 8

c. 6

-->  d. 2

question_image

What element is this?

a. Nitrogen

-->  b. Helium

c. Neon

d. Oxygen

question_image

What is the mass of He?

-->  a. Four

b. Two

c. Six

d. One

question_image

What does the element symbol represent?

a. Hydrodgen

b. Mercury

c. Carbon Dioxide

-->  d. Helium

question_image

What is the atomic number of cobalt?

a. CO2

b. Co

-->  c. 27

d. 59

question_image

Which of the following shows the number of protons in an element?

-->  a. atomic number

b. element symbol

c. mass number

d. melting point

question_image

What is represented in the superior left corner of the diagram?

a. The atomic Number

b. The symbol of the element

c. The charge

-->  d. The mass Number

question_image

What is the atomic number of Co?

a. 21

-->  b. 27

c. 4

d. 59

question_image

An increase of the mass number without a change in the symbol of the element indicates which of the following?

a. A change in the number of electrons

-->  b. A change in the number of neutrons

c. A different element

d. A change in the number of protons

question_image

Symbols of elements are always this character.

a. Numbers

b. Emoji

c. A mixture

-->  d. Letters

question_image

Which among these has the highest atomic number?

-->  a. Tritium

b. Deuterium

c. Protium

d. Protium and Deuterium

question_image

How many H elements are there in an atom?

a. 4

-->  b. 3

c. 5

d. 2

question_image

What is the atomic weight for tritium?

a. 4

b. 2

-->  c. 3

d. 1

question_image

Why is the mass number different for the 3 H elements?

a. because the other H are heavier

b. because they are not the same H

c. because they are different elements

-->  d. because the 2nd and 3rd are isotopes of H

question_image

Which part(s) of an atom create the mass number?

a. protron

b. proton + neutron

-->  c. neutron

d. none

question_image

What's the mass number of Mg?

a. 3

b. 12

c. 2+

-->  d. 24

question_image

As shown in this diagram, what is the atomic number of hydrogen?

a. 24

b. 3

-->  c. 1

d. 12

question_image

How many neutrons does Magnesium (Mg) have? A) 24; B) 12; C) 2; D) 22

a. C) 2

b. A) 24

-->  c. B) 12

d. D) 22

question_image

What is the charge of Mg?

-->  a. 2

b. 3

c. 12

d. 1

question_image

Which among these has a positive charge?

a. Helium

b. Hydrogen

c. Chlorine

-->  d. Magnesium

question_image

What is the atomic number of this atom?

-->  a. 13

b. 40

c. 31

d. 27

question_image

What is the relative atomic mass?

a. 33

b. 1

-->  c. 27

d. 7

question_image

How many protons does this element have?

a. 12

b. 2

c. 3

-->  d. 6

question_image

What makes up the mass number

a. protons and electrons

b. protons only

c. electrons and neutons

-->  d. protons and neutrons

question_image

What is atomic number of Carbon?

a. 8

b. 12

-->  c. 6

d. 4

question_image

How many neutrons are there in the picture below?

a. 2

b. 12

-->  c. 6

d. 4

question_image

According to the diagram, how many electrons does Sodium have on its third electron shell?

a. zero

-->  b. one

c. eight

d. two

question_image

How many protons are on the sodium atom?

a. 8

b. 23

-->  c. 11

d. 12

question_image

What does the number, 23, represent in this diagram?

a. Atomic Number

b. Neutrons Only

c. Protons Only

-->  d. Mass Number

question_image

Identify the part of the diagram that refers to the number of protons in an atom.

-->  a. Atomic Number

b. Symbol

c. Charge

d. Mass Number

question_image

What is the number represented in the upper left of a Chemical Symbol?

a. charge

b. atomic diameter

c. atomic number

-->  d. mass number

question_image

How many elements are shown in this diagram?

a. 4

b. 2

c. 3

-->  d. 1

question_image

How many protons are on the sodium atom?

a. 23

-->  b. 11

c. 22

d. 12

question_image

What is the mass number for Na?

a. 11

b. 12

-->  c. 23

d. +

question_image

What is the atomic number of Molybdenum?

a. 95

-->  b. 42

c. 94

d. 95.94

question_image

What is the atomic number of this element?

a. molybdenum

-->  b. 42

c. Mo

d. 95.94

question_image

What is the atomic symbol of molybdenum?

-->  a. Mo

b. Mb

c. Ma

d. Mm

question_image

How many atomic symbols are there in the diagram?

a. two

b. three

c. four

-->  d. one

question_image

What is the element name of Mo?

a. 95.94

b. Missouri

c. 42

-->  d. molybdenum

question_image

What is the atomic number of the carbon?

a. 4

b. 1

c. 2

-->  d. 6

question_image

Which elemental property is indicated in the upper-left-hand corner of the abbreviated chemical element?

a. Atomic Volume

-->  b. Atomic Mass

c. Atomic Number

d. Atomic Symbol

question_image

How many neutrons does the element Carbon have?

-->  a. 6

b. 8

c. 2

d. 12

question_image

How many numbers are shown in the picture?

a. 7

-->  b. 2

c. 5

d. 1

question_image

Atomic symbols are always...

a. Emoji

-->  b. Letters

c. Letters and numbers

d. Numbers

question_image

What element is being represented in this diagram?

a. Oxygen

b. Helium

-->  c. Carbon

d. Carbon Dioxide

question_image

Identify the Atomic Mass.

a. U

b. 146

c. 92

-->  d. 238

question_image

How many elements of the periodic table are shown in the figure?

a. 2

b. 3

c. 4

-->  d. 1

question_image

How many neutrons does this element have?

-->  a. 146

b. 238

c. 73

d. 92

question_image

What does the positive sign stand for?

a. Electon

b. Neutron

c. Nucleus

-->  d. Proton

question_image

Identify the particle in the nucleus of an atom that has a positive electric charge.

a. Electron

b. Neutron

c. Nucleus

-->  d. Proton

question_image

What particles are positives?

a. Neutron

b. Electron

c. Atoms

-->  d. Protons

question_image

What two types of particles are inside the Nucleus?

-->  a. Protons and Neutrons

b. Protons and Electrons

c. Electrons and Neutrons

d. Ions and Electrons

question_image

Which of these don't belong inside the nucleus?

a. protons

b. neither of them

-->  c. electrons

d. neutrons

question_image

How many parts of an atom are there?

a. 3

-->  b. 4

c. 1

d. 2

question_image

How many protons does this atom's nucleus contain?

a. 9

b. 5

-->  c. 4

d. 13

question_image

What charge does a proton have inside an atom?

-->  a. Positive charge

b. Neutral charge

c. Negative charge

d. Positive and negative charge

question_image

Where are the neutrons and protons contained?

a. Atom

b. Electrons

-->  c. Nucleus

d. Neutron

question_image

Which ion is not in the nucleus?

-->  a. Electrons

b. Ions

c. Protons

d. Neutrons

question_image

The structure electrons surround is known as which of the following?

a. neutron

b. proton

-->  c. nucleus

d. atom

question_image

Which charged particle is not in the nucleus of an atom?

-->  a. electron

b. photon

c. neutron

d. proton

question_image

How many particles with no electric charge are there in this picture?

a. 6

b. 7

-->  c. 8

d. 9

question_image

In this diagram, the nucleus contains protons and what?

a. Electrons

-->  b. Neutrons

c. Atoms

d. Membranes

question_image

What charge do electrons have?

a. none

b. positive

c. neutral

-->  d. negative

question_image

What particles are found in the nucleus?

a. Electrons & protons

b. Electrons & neutrons

c. Electrons

-->  d. Protons & neutrons

question_image

How many electron clouds are depicted?

-->  a. 1

b. 4

c. 3

d. 2

question_image

What is used to describe where electrons are when they go around the nucleus of an atom?

-->  a. Electron Cloud

b. Nucleus

c. Electron

d. Protons

question_image

What kind of charge does a Proton hold?

a. Negative

b. No Charge

c. Neutral

-->  d. Positive

question_image

Which item would emit energy and spirally fall on the nucleus?

a. Neutron

b. Atom

c. Proton

-->  d. Electron

question_image

What is the negative part of an atom?

-->  a. Electron

b. Proton

c. Neutron

d. Croton

question_image

Which part of the atom contains most of the atom's mass?

a. Proton

-->  b. Nucleus

c. Electron

d. Neutron

question_image

What particles can be found inside the nucleus?

a. Electrons and Protons

-->  b. Protons and Neutrons

c. Electrons

d. Protons Only

question_image

How many elements are there in an atom?

-->  a. 4

b. 3

c. 2

d. 5

question_image

How many Neutrons are shown here?

a. 4

-->  b. 2

c. 1

d. 3

question_image

What is not contained in nucleus?

a. Proton

b. Neotron

c. Many protons

-->  d. electron

question_image

Which of the following can be found inside of a Proton?

-->  a. Quark

b. Nucleus

c. Electron

d. Neutron

question_image

Which particles are contained in the nucleus of an atom?

a. electron and neutron

-->  b. neutron and proton

c. neutron only

d. proton and electron

question_image

How many electrons are represented?

a. 1

-->  b. 3

c. 4

d. 2

question_image

How many protons are in the diagram?

a. 6

b. 7

c. 8

-->  d. 3

question_image

How is the neutron electrically neutral?

a. it doesn't have positive charge

b. it has no charge at all

-->  c. its negative and positive charges cancel out

d. it doesn't have a negative charge

question_image

How many electrons are in the atom below?

a. 9

b. 5

-->  c. 8

d. 6

question_image

Which part of the atom contains most of the atom's mass?

a. neutron

b. proton

-->  c. nucleus

d. electron

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What is the relationship between the number of protons and the number of electrons?

a. There is always one more proton than electron

-->  b. There is the same number of them

c. There is no relation

d. There is always double the number of electrons than the number of protons

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Which part of the atom is negatively charged?

a. Neutron

-->  b. Electron

c. Nucleus

d. Proton

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How many protons are shown in the diagram?

a. 3

b. 5

c. 4

-->  d. 6

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Which of the following is not a part of an atom?

-->  a. electrode

b. electron

c. proton

d. nucleus

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Which particle has a positive electric charge?

a. Nucleus

-->  b. Proton

c. Electron

d. Neutron

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How many electrons are in the diagram?

-->  a. 3

b. 4

c. 2

d. 1

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How many neutrons are present in nucleus?

-->  a. 3

b. 2

c. 1

d. 4

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How many electrons are represented on the outer shell?

a. 6

b. 3

-->  c. 4

d. 2

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How many electrons orbit the nucleus?

a. 7

b. 4

c. 5

-->  d. 6

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What is the charge of the electron in reference to the proton?

a. more negative

b. more positive

-->  c. The charge of an electron is opposite but equal to the charge of a proton. Atoms have the same number of electrons as protons. As a result, the negative and positive charges "cancel out."

d. they are the same

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What particles are surrounding the proton?

a. neutron

b. atom

-->  c. valence electron

d. nucleus

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How many valence electrons are present in the atom?

-->  a. 4

b. 3

c. 2

d. 1

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Silicon as how many valence electrons?

a. 6

-->  b. 4

c. 8

d. 2

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Identify the most condensed part of an atom

-->  a. Nucleus

b. Nucleolus

c. Shell K

d. Photons

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Which of the particles gives unique properties to elements?

-->  a. proton

b. neutron

c. electron

d. nucleus

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Where are electrons located?

a. Inside the nucleus

b. Next to the neutrons

c. Inside and outside the nucleus

-->  d. Outside the nucleus

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How many electrons are in this diagram?

-->  a. 13

b. 12

c. 11

d. 8

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How many protons are shown in the diagram?

a. 6

-->  b. 7

c. 2

d. 4

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What is the nucleous made of?

a. Electrons and Neutrons

-->  b. Protons and Neutrons

c. Protons and Electrons

d. Electrons Only

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What is the center of an atom called?

-->  a. Nucleus

b. Neutron

c. Proton

d. Electron

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Which particles can be found in the nucleus?

-->  a. Protons and neutrons

b. Electrons and Neutrons

c. Electrons and protones

d. Neutrons only

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What attracts the electron to the nucleus?

a. Neutron

b. Electron

c. Nucleus

-->  d. Proton

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How many electrons are in the image?

a. 1

-->  b. 3

c. 2

d. 8

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How many parts are there in an atom?

a. 2

b. 5

c. 3

-->  d. 4

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Atoms of each type of element have a characteristic number of what particle?

a. electrons

b. neutrons

-->  c. protons

d. nucleus

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How many electrons are in the diagram?

-->  a. 6

b. 7

c. 12

d. 5

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How many protons are there in a carbon atom?

a. 12

b. 7

c. 5

-->  d. 6

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Can a carbon atom still be formed if 2 protons and 2 neutrons are removed?

a. Yes

-->  b. No

c. Cannot determine from the given information

d. Maybe

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Identify the atomic number of Hydrogen

a. 3

-->  b. 1

c. 2

d. 4

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The amount of which particle determines if an atom is an isotope?

a. Proton

b. Electron

-->  c. Neutron

d. Hydrogen

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What did we add to protium for it to become deuterium?

a. A proton

b. Atomic number

-->  c. A neutron

d. An electron

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What does the plus (+) symbol signify?

-->  a. Protons

b. Neutrons

c. Nucleus

d. Electrons

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How many neutrons raise the atomic weight by 2?

-->  a. 2

b. 4

c. 1

d. 5

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What is the atomic weight of all the isotopes depicted in the diagram added together? A) 38; B) 39; C) 40; D) 41

a. C) 40

b. A) 38

c. D) 41

-->  d. B) 39

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What would be the atomic weight of a carbon 15 atoms?

a. 22

b. 11

c. 14

-->  d. 15

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Which has 2 extra neutrons?

a. Unstable Carbon Atom

b. Stable Carbon Atom

-->  c. Unstable- Radioactive Carbon Isotope

d. Stable Carbon Isotope

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What do the two extra neutrons do to the carbon atom?

a. They cause the number of electrons to increase

-->  b. They make it unstable

c. There are no two extra neutrons

d. They do not affect it

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Which carbon isotope has an extra neutron?

-->  a. stable carbon isotope

b. unstable carbon isotope

c. unstable carbon atom

d. stable carbon atom

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From the diagram, how many carbon isotopes are there?

-->  a. 2

b. 1

c. 3

d. 0

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How many extra neurons does the unstable carbon isotope have?

-->  a. 2

b. 3

c. 4

d. 1

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What do you call a subatomic particle with a symbol p or p+?

a. Electron

-->  b. Proton

c. Neutron

d. Carbon

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What makes the oxygen stable?

a. proton

b. neutron

c. valence shell electron

-->  d. energy configuration

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How many protons do the two atoms have in total?

a. 10

-->  b. 16

c. 18

d. 8

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Oxygen 16 and 18 are called what?

-->  a. Isotopes

b. Protons

c. Ions

d. Neutrons

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Oxygen-16 has how many protons?

a. 12

b. 6

-->  c. 8

d. 10

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Deuterium has how many electrons?

a. 4

b. 2

-->  c. 1

d. 3

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How many electrons are there in Deuterium?

-->  a. 1

b. 2

c. 3

d. 4

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Identify which has eight neutrons.

a. Carbon-13

-->  b. Carbon-14

c. Carbon-15

d. Carbon-12

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What falls between carbon-12 and carbon-14?

-->  a. carbon-13

b. carbon-11

c. carbon-15

d. carbon-10

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What's the difference between carbon-12 and carbon-13?

a. One has one more neutron

b. None

-->  c. One has one more proton than the other

d. One has two more protons

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How many neutrons are found in Carbon-14?

a. 14

-->  b. 8

c. 7

d. 6

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How many protons does carbon-12 contain?

a. 5

-->  b. 6

c. 8

d. 7

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The following forms of Carbon are called what?

a. Chiral molecules

b. Ions

c. Isomers

-->  d. Isotopes

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How many neutrons does Tritium have?

-->  a. 3

b. 2

c. 1

d. 4

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Adding the number of protons and neutrons will result to:

-->  a. Mass Number

b. Number of ions

c. Atomic Number

d. Number of electrons

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Which is radioactive?

a. Carbon-13

b. Stable

c. Carbon-12

-->  d. Carbon-14

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Based on the stable carbon 12 how does the neutron change when it becomes radioactive?

a. decreases

b. doubles

c. stays the same

-->  d. increases by 2

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How many protons are in carbon-13?

a. 2

b. 5

-->  c. 6

d. 8

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How many electrons are in all three of the atoms pictured?

a. 13

-->  b. 6

c. 14

d. 12

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How many neutrons are in an unstable carbon atom?

a. 7

b. 14

-->  c. 8

d. 6

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How many neutrons does carbon-13 have?

-->  a. 7

b. 6

c. 9

d. 8

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How many molecules are?

a. 6

b. 4

-->  c. 2

d. 3

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How many neutrons are there in carbon-13?

a. 8

b. 5

-->  c. 7

d. 6

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How many neutrons does carbon-13 have?

a. 8

b. 6

c. 9

-->  d. 7

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What does the green circle represent?

a. Carbon

b. Atom

c. Neutron

-->  d. Proton

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What does hydrogen become if one adds two neutrons to it?

a. leuterium

b. quaternion

c. deuterium

-->  d. tritium

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How many neutrons does hydrogen have?

a. 1

b. 2

-->  c. zero

d. 3

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Which of these 3 atoms would be the heaviest?

-->  a. Tritium

b. Deuterium

c. Data Insufficient?

d. Hydrogen

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How many neutrons does the 18O Isotope have?

-->  a. 10

b. 9

c. 2

d. 6

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How many protons do the oxygen isotopes in the diagram have?

a. 16

b. 9

c. 10

-->  d. 8

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What is the atomic mass of Al?

-->  a. 27

b. 13

c. 30

d. 33

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What is the atomic number of the protium?

-->  a. 1

b. 3

c. 4

d. 2

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Which has the higher N

a. 16o

b. 8P

-->  c. 18o

d. 14o