Chemistry Unit 2 Review

Question 1

October 2013: Mr. LB is...

Accepted Answer

Walter White

Question 2

How many electrons are in the second energy level of a neutral oxygen atom?

Accepted Answer

6

Question 3

Atoms A and B are:

Accepted Answer

isotopes

Question 4

How many neutrons does an atom 235U have (uranium-235)?

Accepted Answer

143

Question 5

The wavelengths observed in the hydrogen line emission spectrum are caused by:

Accepted Answer

different energy level transitions by H's electron

Question 6

Observations of the phenomenon shown in this video led Bohr to propose that:

Accepted Answer

electrons have certain orbits with specific energy levels

Question 7

Which neutral atom has the electron configuration 1s22s22p63s1?

Accepted Answer

Na

Question 8

The number of protons in an atom is called the:

Accepted Answer

atomic number

Question 9

How many protons are in an atom of chlorine-35?

Accepted Answer

17

Question 10

How is charge calculated?

Accepted Answer

protons minus electrons

Question 11

What is the electron configuration of nickel?

Accepted Answer

1s22s22p63s23p64s23d8

Question 12

October 2011: Mr. LB is...

Accepted Answer

the engineer from TF2

Question 13

The sum of the protons and neutrons in an atom is called the:

Accepted Answer

mass number

Question 14

How many valence electrons does potassium have?

Accepted Answer

1

Question 15

If it has 14 protons and 18 electrons, it is:

Accepted Answer

an ion

Question 16

A row on the periodic table is called a:

Accepted Answer

period

Question 17

Which atom or ion would NOT have this arrangement of electrons?

Accepted Answer

Mg2-

Question 18

Atoms B and C are:

Accepted Answer

different elements

Question 19

Which one is an ion?

Accepted Answer

D

Question 20

In a hydrogen atom, when an electron drops from level n=4 to n=2, what color photon is emitted?

Accepted Answer

green

Question 21

A sodium ion has a charge of +1. How many electrons does it have?

Accepted Answer

10

Question 22

Dalton's 1805 atomic theory held that atoms are:

Accepted Answer

combined, separated, or rearranged by chemical reactions

Question 23

The first experiment to prove that atoms are made of smaller parts was:

Accepted Answer

the cathode ray experiment

Question 24

In a hydrogen atom, when an electron drops from level n=6 to n=2, what color photon is emitted?

Accepted Answer

violet

Question 25

What did this experiment reveal?

Accepted Answer

an atom's mass is concentrated in the nucleus

Question 26

An neutral atom has the following arrangement of electrons. Which element is it?

Accepted Answer

S

Question 27

How many valence electrons does selenium have?

Accepted Answer

6

Question 28

A region of space around the nucleus where an electron has a high probability of being:

Accepted Answer

orbital

Question 29

A carbon atom has the same number of energy levels as:

Accepted Answer

B

Chemistry Unit 2 Review

Questions 29

Chemistry Unit 2 Review

Questions 29