Atoms and IsotopesBy Ryan Goldberg and Jack Lane

Atoms Atomic Mass/Number

Ions/Charges of Molecules

Isotopes/Percent

Abundance

10 10 10 10

20 20 20 20

30 30 30 30

40 40 40 40

50 50 50 50

Question 1 - 10

Define an atom.

Answer 1 – 10

The basic unit of a chemical element

Question 1 - 20

Where is most of the mass of an atom located?

Answer 1 – 20

Nucleus

Question 1 - 30

Using a cathode ray tube, JJ Thompson discovered what subatomic particle?

Answer 1 – 30

Electrons

Question 1 - 40

An element contains atoms with the same number of what subatomic particle?

Answer 1 – 40

Protons

Question 1 - 50

What is a molecule?

Answer 1 – 50

Two or more atoms with a definite arrangement held together by chemical bonds.

Question 2 - 10

The atomic number of an atom is equal to what?

Answer 2 – 10

Protons

Question 2 - 20

Calculate the atomic mass of Oxygen with 10 neutrons.

Answer 2 – 20

18

Question 2 - 30

Element X has an atomic number of 15 and an atomic mass of 37. How many neutrons does element X have?

Answer 2 – 30

22

Question 2 - 40

What is the unit used for measuring the mass of atoms.

Answer 2 – 40

Atomic mass units (amu)

Question 2 - 50

What is the atomic number of Calcium? If Calcium has 24 neutrons, what is its atomic mass?

Answer 2 – 50

The atomic number is 20, and its mass is 44.

Question 3 - 10

Define an ion.

Answer 3 – 10

An atom with a net positive or negative charge.

Question 3 - 20

What is the difference between anions and cations?

Answer 3 – 20

Anions have a negative charge and cations have a positive charge.

Question 3 - 30

What two subatomic particles must be equal in order to create a neutral atom?

Answer 3 – 30

Protons and Electrons

Question 3 - 40

How many electrons are in S-2?

Answer 3 – 40

18 electrons

Question 3 - 50

Which atom has more electrons? Mg+1 or O-

2?

Answer 3 – 50

Mg+1

Question 4 - 10

Define isotope

Answer 4 – 10

Atoms of the same element with different numbers of neutrons resulting in different atomic masses.

Question 4 - 20

How many neutrons are in a Carbon isotope with a mass of 20?

Answer 4 – 20

8 neutrons

Question 4 - 30

Calculate the average atomic mass of these two Nitrogen isotopes: 95% 14N and 5% 15N.

Answer 4 – 30

14.05 amu

Question 4 - 40

Calculate the average atomic mass of these three isotopes of Oxygen: 78% 16O, 8% 17O, 14% 18O.

Answer 4 – 40

16.36 amu

Question 4 - 50

There are three isotopes of Silicon: 84% 28Si, 10% 29Si, 6% 30Si. A: How many neutrons does each isotope have? B: What is the average atomic mass? (Silicon has an atomic number of 14)

Answer 4 – 50

A: 1) 14 2) 15 3) 16 B: 28.22 amu