Unit 3: Atomic Theory Test Review

Question 1

How did the cathode ray experiment change atomic theory?

Accepted Answer

It lead to the discovery of the negative electrons

Question 2

How many protons does potassium have?

Accepted Answer

19

Question 3

An isotope that contains 35 protons and 45 neutrons would be written as:

Accepted Answer

bromine-80

Question 4

The gold foil experiment lead to the discovery of which subatomic particle?

Accepted Answer

Proton

Question 5

Which of the following statements accurately represents the location of neutrons?

Accepted Answer

All neutrons are in the nucleus

Question 6

How many electrons would there be in a scandium ion with a +3 charge?

Accepted Answer

18

Question 7

Which of the following best describes ions?

Accepted Answer

Same element, different number of electrons

Question 8

Which of the following has the largest mass in an atom?

Accepted Answer

Nucleus

Question 9

How many neutrons are in Nitrogen-15?

Accepted Answer

8

Question 10

Which law states that a compound will always have the same percentage composition by mass?

Accepted Answer

Law of Definite Proportions

Question 11

The identity of an element can be determined based on ______________

Accepted Answer

The number of protons

Question 12

How many electrons are in Arsenic-76?

Accepted Answer

33

Question 13

How many neutrons does strontium have if the mass number is 89?

Accepted Answer

51

Question 14

Which scientist developed a summary of atomic theory which included an indivisible atom?

Accepted Answer

John Dalton

Question 15

How many electrons are in the final shell of a Bohr model for neutral sodium?

Accepted Answer

1

Question 16

You can never form a compound with the formula MgO1.5. Which law explains this?

Accepted Answer

Law of Multiple Proportions

Question 17

Which of the following accurately describes the Rutherford model of the atom?

Accepted Answer

Nucleus at the center and the atom is mostly empty space

Question 18

How many electrons will be in the final shell of a Bohr model for nitrogen with a -3 charge?

Accepted Answer

8

Question 19

How many neutrons are in a scandium ion with a +3 charge?

Accepted Answer

24

Question 20

What is the hyphen notation for an isotope with 7 protons, 8 neutrons, and 7 electrons?

Accepted Answer

Nitrogen-15

Questions 20