Fall 2019 Chemistry Final Exam Review

Random 1

100

How many valence electrons does neon have?

8

200

What is the chemical formula of iron(III) hydroxide? 

a. Fe(OH)₂

b. Fe(OH)₃

c. Fe₃(OH)

d. Fe₂(OH)₃

b. Fe(OH)₃

300

Electronegativity values for elements in Group 1A are much lower than the values for elements in Group 7A. What type of bond forms if an element form Group 1A bonds with an element from Group 7A?

a. ionic bond

b. hydrogen bond

c. polar covalent bond

d. nonpolar covalent bond 

a. ionic bond 

400

The ions in calcium chloride dissociate in the presence of water. What is the cation that is produced in this reaction?

a. H⁺

b. O^2-

c. Ca²⁺

d. Cl^-

c. Ca²⁺

500

Calculate the percent composition of ammonium nitrate, NH₄NO₃.

35% N, 5% H, 60% O

Random 2

100

What is the chemical formula of the phosphate ion?

a. PO₄^-

b. HPO₄^2-

c. H₂PO₄^2-

d. PO₄^3-

d. PO₄^3-

200

Calculate the percent composition of a compound that is formed by 32 g of Oxygen and 4 g of Hydrogen. 

O: 88.9%

H: 11.1%

300

Chlorine (Cl) is found in group 17 (7A) of the periodic table. Chlorine is commonly found combined with sodium (Na) to form table salt (NaCl). When chlorine reacts with sodium, how many electrons will a chlorine atom gain or lose?

a. gain one electron

b. lose one electron

c. gain two electrons

d. lose two electrons

a. gain one electron

400

What would be the precipitate in the reaction below?

ZnSO₄ + 2AgCl --> Ag₂SO₄ + ZnCl₂

a. Ag₂SO₄

b. ZnCl₂

c. Ag₂SO₄ and ZnCl₂

d. no precipitate will form

a. Ag₂SO₄

500

A compound is analyzed and determined to be 30.4% nitrogen and 69.6% oxygen. What is the empirical formula of the compound?

NO₂

Random 3

100

How many valence electrons does boron (B) have?

3

200

A neutral chlorine atom contains 17 protons and 18 neutrons. How many electrons are there in a chlorine ion (Cl^1-)?

a. 17

b. 18

c. 34

d. 35

b. 18

300

Calculate the percent composition of Mg₃(PO₄)₂.

Mg: 27.5%

P: 23.7%

O: 48.9%

400

A neutral atom of a certain element has the electron configuration 1s²2s²2p⁶3s²3p⁴. How many valence electrons does the atom have?

a. 4

b. 6

c. 11

d. 16

b. 6

500

What mass of hydrogen sulfide, H₂S, will completely react with 2.00 moles of silver nitrate, AgNO₃.

2AgNO₃ + H₂S --> Ag₂S + 2HNO₃

34.1 grams

Random 4

100

Why are metals good conductors of thermal energy?

a. the randomly arranged atoms in metals increase the ability to transmit heat

b. the atoms in metals can easily convert chemical energy into kinetic energy

c. the freely moving electrons in atoms transfer kinetic energy throughout the metal

d. the electronegativity difference between atoms in metals allows heat to flow easily 

c. the freely moving electrons in atoms transfer kinetic energy throughout the metal

200

What is the name of the following compound: HCl?

a. hydrochloric acid

b. chloric acid

c. chlorous acid

d. hydrogen chloride 

a. hydrochloric acid

300

Beryllium has two valence electrons. When beryllium reacts with some other elements, it becomes an ion. What is the charge of a beryllium ion?

a. -4

b. -2

c. +2

d. +4

c. +2

400

In the electron cloud model of the atom, what does the cloud represent?

a. the limits of the electron location

b. the probability of the electron location

c. the average distance between the electron and the nucleus

d. the minimum distance between the electron and the nucleus 

b. the probability of the electron location 

500

Nitrogen and hydrogen react to produce ammonia.

N₂ + 3H₂ --> 2NH₃

How many grams of hydrogen are needed to produce 15.0 mol of ammonia if the reaction goes to completion?

45.0 g

Random 5

100

Which molecule contains a triple bond?

a. F₂

b. O₂

c. Cl₂

d. N₂

d. N₂

200

What is the correct name for the compound whose formula is Fe₂O₃?

a. iron oxide

b. iron trioxide

c. iron(II) oxide

d. iron(III) oxide

d. iron(III) oxide

300

Chlorine is a highly reactive element. It tends to gain one electron to become more stable. How does gaining one electron make chlorine more stable?

a. stability is increased with greater mass

b. mobility is reduced in atoms with extra electrons

c. the other energy level becomes the same as a noble gas

d. the most stable ratio of electrons to protons is achieved 

c. the outer energy level becomes the same as a noble gas

400

A student has a homework assignment to identify the properties of an element based on its electron configuration. If the element has an electron configuration of 1s²2s²2p⁶3s²3p⁶4s²3d¹⁰4p⁵, which of the following MOST likely a property of this element?

a. low ionization energy

b. forms ions with a 2- charge

c. good electricity conductor

d. forms salt with sodium (Na)

d. forms salt with sodium (Na)

500

How many molecules of methane are produced by the combustion of 3.00 g of methane?

CH₄ + 2O₂ --> CO₂ + 2H₂O

1.13 x 10²³ molecules