Unit 2

Question 1

Ernest Rutherford determined that the ____ held a ____ charge that was surrounded by mostly empty space from “gold foil experiment”

Answer 1

nucleus; positive

Question 2

J.J. Thomson used a cathode ray tube to confirm the existence of which subatomic particle?

Answer 2

Electrons

Question 3

In Niels Bohr’s atomic model, electrons are located in ______.

Answer 3

orbits

Question 4

Dalton theorized that the atoms are indivisible and that all atoms of an element are identical. We now know that ___.

Answer 4

Atoms are divisible (can be broken down further)

Question 5

Who first arranged the elements according to atomic mass and noticed a periodic recurrence of their physical and chemical properties?

Answer 5

Dmitri Mendeleev

Question 6

What is the smallest particle of an element that retains the properties of that element?

Answer 6

an atom

Question 7

Hydrogen-4 has how many electrons in a neutral atom?

Answer 7

1

Question 8

Hydrogen-4 has how many neutrons?

Answer 8

3

Question 9

Hydrogen-4 has how many protons?

Answer 9

1

Question 10

Sulfur-34 has how many protons?

Answer 10

16

Question 11

Sulfur-34 has how many electrons in a neutral atom?

Answer 11

16

Question 12

Sulfur-34 has how many neutrons?

Answer 12

18

Question 13

The atomic number of an element is equal to the number of which particles in the nucleus?

Answer 13

protons

Question 14

The sum of the protons and neutrons in an atom equals the ___

Answer 14

mass number

Question 15

Which subatomic particle has a positive charge?

Answer 15

proton

Question 16

Which two subatomic particles are found in the nucleus of an atom?

Answer 16

proton and neutron

Question 17

Two isotopes of an element are exactly the same except for the

Answer 17

neutrons

Question 18

What does the letter “Na” represent. (look at the image)

Answer 18

element symbol

Question 19

What does the letter “A” represent? (look at the image)

Answer 19

mass number

Question 20

What does the letter “Z” represent? (look at the image)

Answer 20

atomic number

Question 21

True or False: Atoms of isotopes of an element have different numbers of protons.

Answer 21

false (they have different numbers of neutrons)

Question 22

Which subatomic particles have a mass of 1 amu?

Answer 22

protons and neutrons

Question 23

All atoms of the same element have the same

Answer 23

number of protons

Question 24

What is the average atomic mass for the isotopes carbon-12 with an abundance of 96.0% & carbon-14 with an abundance of 4.0%?

Answer 24

12 amu

Question 25

Find the average atomic mass of silver if 52% of the silver atoms are 107 Ag and the rest are 109 Ag.

Answer 25

107.96

Question 26

Why are all atomic masses not nearly whole numbers?

Answer 26

This is because atomic masses are the the weighted average of the masses of all naturally occurring isotopes.

Question 27

How many valence electrons are in an alkali metal?

Answer 27

1

Question 28

How many valence electrons are in a halogen?

Answer 28

7

Question 29

What is the alkaline earth metal found in period 2?

Answer 29

Be

Question 30

What type of metal is Fe?

Answer 30

Transition metal

Question 31

Which of the following (Ag, Cu, S, Si) is a metalloid?

Answer 31

Si

Question 32

How many valence electrons does an atom of bromine have?

Answer 32

7

Question 33

How many valence electrons does an atom of magnesium have?

Answer 33

2

Question 34

The Lewis dot structure for an element in the Halogen family will have how many dots around each atom's symbol?

Answer 34

7

Question 35

How many valence electrons would be found in an atom with the atomic number of 51?

Answer 35

5

Question 36

How many rings are in the Bohr diagram of a Fluorine atom?

Answer 36

2

Question 37

Experiments with cathode rays led to the discovery of the \_\_\_.

Answer 37

electron

Question 38

A positive ion is known as a(n)

Answer 38

cation

Question 39

A negative ion is known as a(n)

Answer 39

anion

Question 40

Rubidium has two common isotopes, rubidium-85 and rubidium-87. If the abundance of Rubidium-85 is 70.00% and Rubidium-87 is 30.00%, what is the average atomic mass of rubidium?

Answer 40

85.60 amu

Question 41

Nickel-58 (atomic number 28) has how many neutrons?

Answer 41

30

Question 42

Sulfur-36 (atomic number 16) contains how many neutrons?

Answer 42

20

Question 43

Neon-20 contains 10 neutrons. It also contains ___ protons.

Answer 43

10

Question 44

Look at the diagram. It is a Bohr model of what element?

Answer 44

Sodium

Question 45

Look at the diagram. It is a Bohr model of what element?

Answer 45

Boron

Question 46

Which subatomic particle has the least mass?

Answer 46

electron