gen chem one final

Question 1

An atom of Kr-84 contains _____ protons.

Answer 1

36 protons

Question 2

Different isotopes of a particular element contain the same number of _____.

Answer 2

protons

Question 3

The formula for calcium nitrate is Ca(NO₃)₂. The molecular weight of this compound is:

Answer 3

164.10 g/mol

Question 4

The mass % of C in sucrose (C₁₂H₂₂O₁₁) is:

Answer 4

42.11%

Question 5

An object measuring 725 grams will have a mass of _____ kilograms.

Answer 5

0.725 kg

Question 6

The density of lead is 11.3 g/cm³. A piece of lead with a mass of 22.1 g would occupy a volume of _____ cm³.

Answer 6

1.96 cm³

Question 7

Metals and nonmetals form what type of compounds?

Answer 7

Ionic compounds

Question 8

Name the ionic compound MgS.

Answer 8

Magnesium sulfide

Question 9

Name the compound S₂Cl₂.

Answer 9

Disulfur dichloride

Question 10

Name the compound SnCl₄.

Answer 10

Tin(IV) chloride

Question 11

What is the formula for calcium nitrate?

Answer 11

Ca(NO₃)₂

Question 12

Reduction cannot occur without:

Answer 12

Oxidation

Question 13

What volume (mL) of a 6.0 M calcium hydroxide solution must be diluted to 150.0 mL to make a 0.750 M solution?

Answer 13

18.75 mL

Question 14

Calculate the molarity of a solution prepared by dissolving 1.495 moles of Ca(OH)₂ in 500 mL of water.

Answer 14

2.99 M

Question 15

Calculate the number of moles of solute in 2.500 L of 3.52 M LiOH solution.

Answer 15

8.80 mol

Question 16

Which element is oxidized and which is reduced in the reaction:
Cl₂ (aq) + 2NaI (aq) → I₂ (aq) + 2NaCl (aq)?

Answer 16

Oxidized: Iodine (I⁻ → I₂)

Reduced: Chlorine (Cl₂ → Cl⁻)

Question 17

How many moles of HCl are required to react with 0.62 mol Ca(OH)₂?

Answer 17

1.24 mol HCl

Question 18

The ΔE of a system that gains 24.6 J of heat and does 4.2 J of work on the surroundings is _____ J.

Answer 18

20.4 J

Question 19

Internal energy can be increased by:

Answer 19

Adding heat or doing work on the system

Question 20

ΔH for an endothermic process is ____ while ΔH for an exothermic process is _____.

Answer 20

Positive; Negative

Question 21

How many moles of MgO are produced during an enthalpy change of -234 kJ?

Answer 21

0.39 mol MgO

Question 22

Si and C have the same number of _____ electrons.

Answer 22

Valence

Question 23

Define effective nuclear charge.

Answer 23

The net positive charge experienced by an electron in a multi-electron atom; accounts for shielding by inner electrons.

Question 24

Give the electron configuration for sulfur.

Answer 24

1s² 2s² 2p⁶ 3s² 3p⁴

Question 25

What is the wavelength of light with a frequency of 2.6 × 10¹⁴ s⁻¹ (in meters)?

Answer 25

1.15 × 10⁻⁶ m

Question 26

What is the wavelength of a photon with an energy of 6.45 × 10⁻¹⁹ J?

Answer 26

3.08 × 10⁻⁷ m

Question 27

The element that corresponds to 1s² 2s² 2p⁴ is _____.

Answer 27

Oxygen (O)

Question 28

What are the periodic trends in ionization energy?

Answer 28

Increases across a period, decreases down a group

Question 29

Of the following: F, F⁺, F⁻ — pick the smallest.

Answer 29

F⁺

Question 30

Which has the smallest atomic size? Na, Ar, K, Ca, Kr

Answer 30

Ar

Question 31

Elements in a group have similar _____.

Answer 31

chemical properties

Question 32

What is the trend in atomic size?

Answer 32

Increases down a group; decreases across a period

Question 33

What is ionization energy?

Answer 33

The energy required to remove an electron from a gaseous atom

Question 34

Which element is the most electronegative? F, Mg, P, Cl

Answer 34

F (Fluorine)

Question 35

Which species has the greatest number of electrons? Cl⁻, Ca²⁺, P³⁻, K, Ar

Answer 35

P³⁻ (18 electrons)

Question 36

In CO₂, how many lone pairs are on each oxygen atom?

Answer 36

2 lone pairs

Question 37

The oxidation number of Cu in Cu₂O is:

Answer 37

+1

Question 38

Fluorine's Lewis symbol has ____ paired and _____ unpaired electrons.

Answer 38

3 paired, 1 unpaired

Question 39

What is the molecular geometry of water?

Answer 39

Bent

Question 40

An electron domain consists of:

Answer 40

A lone pair or a bond (single, double, or triple)

Question 41

What is the electron domain geometry of SF₂?

Answer 41

Tetrahedral

Question 42

A gas (3.0 mol) at 2 atm is expanded isothermally from 15 L to 17 L. Final pressure = ?

Answer 42

1.76 atm

Question 43

A gas at 25°C and 1.0 atm in a 2.0 L flask is cooled to 11°C. New volume = ?

Answer 43

1.90 L

Question 44

A gas (1.5 mol) occupies _____ L at 25°C and 2.0 atm?

Answer 44

18.4 L

Question 45

A real gas behaves most like an ideal gas under conditions of:

Answer 45

High temperature and low pressure