Chemistry Chapter 4: Compounds and Stoichiometry (2 Stars)

Question 1

_______ are substances composed of two or more elements in a fixed proportion.

Answer 1

Compounds

Question 2

_________ is the mass (in amu) of the constituent atoms in a compound as indicated by the molecular formula.

Answer 2

Molecular weight

Question 3

________ is the mass of one mole (Avogadro’s number or 6.022 × 10^23 particles) of a compound; usually measured in grams per mole.

Answer 3

Molar mass

Question 4

Gram equivalent weight is a measure of the _____of a substance that can donate one equivalent of the species of interest.

Answer 4

mass

Question 5

_______ is the ratio of equivalents per liter; it is related to molarity by multiplying the molarity by the number of equivalents present per mole of compound.

Answer 5

Normality

Question 6

_______ are moles of the species of interest; ________ are most often seen in acid–base chemistry (hydrogen ions or hydroxide ions) and oxidation– reduction reactions (moles of electrons or other ions).

Answer 6

Equivalents

Question 7

The law of _______ states that any pure sample of a compound will contain the same elements in the same mass ratio.

Answer 7

constant composition

Question 8

The ________ formula is the smallest whole-number ratio of the elements in a compound.

Answer 8

empirical

Question 9

The _______ formula is either the same as or a multiple of the empirical formula; it gives the exact number of atoms of each element in a compound.

Answer 9

molecular

Question 10

To calculate percent composition by mass, determine the mass of the individual element and divide by the ______ of the compound.

Answer 10

molar mass

Question 11

_______ reactions occur when two or more reactants combine to form one product.

Answer 11

Combination

Question 12

__________ reactions occur when one reactant is chemically broken down into two or more products.

Answer 12

Decomposition

Question 13

________ reactions occur when a fuel and an oxidant (typically oxygen) react, forming the products water and carbon dioxide (if the fuel is a hydrocarbon).

Answer 13

Combustion

Question 14

Displacement reactions occur when one or more atoms or ions of one compound are ______ with one or more atoms or ions of another compound.

Answer 14

replaced

Question 15

_________ reactions occur when an ion of one compound is replaced with another element.

Answer 15

Single-displacement

Question 16

Double-displacement reactions occur when elements from #_____ different compounds trade places with each other to form two new compounds.

Answer 16

two

Question 17

__________ reactions are those in which an acid reacts with a base to form a salt (and, usually, water).

Answer 17

Neutralization

Question 18

Balanced equations are determined using the following steps in order: (4)

Answer 18

Balanced equations are determined using the following steps in order:

Balancing the least common atoms.

Balancing the more common atoms (usually hydrogen and oxygen).

Balancing charge, if necessary.

Question 19

Balanced equations can be used to determine the _________, which is the reactant that will be consumed first in a chemical reaction.

Answer 19

limiting reagent

The other reactants present are termed excess reagents.

Question 20

________ is the amount of product generated if all of the limiting reactant is consumed with no side reactions.

Answer 20

Theoretical yield

Question 21

________ is typically lower than theoretical yield.

Answer 21

Actual yield

Question 22

_________ is calculated by dividing actual yield by theoretical yield and converting to a percentage.

Answer 22

Percent yield

Question 23

–ous endings can also be used to indicate _____charge, while –ic endings indicate _____charge.

Answer 23

lesser
greater

Question 24

All monatomic anions end in –____

Answer 24

–ide.

Question 25

\_\_\_\_\_\_ are given a suffix indicating how oxidized the central atom is. Those that contain a lesser amount of oxygen are given the suffix –ite, and those with a greater amount are given the suffix –ate.

Answer 25

Oxyanions

Question 26

The species with the fewest oxygens is given the prefix \_\_\_\_–, and the species with the most oxygens is given the prefix per–.

Answer 26

hypo–

Question 27

\_\_\_\_\_\_\_\_ containing hydrogen denote the number of hydrogens using hydrogen or bi– to denote one, or dihydrogen to denote two.

Answer 27

Polyatomic ions

Question 28

\_\_\_\_\_\_\_ are predictable by group number and type of element (metal or nonmetal) for representative elements, but are generally unpredictable for nonrepresentative elements.

Answer 28

Ionic charges

Question 29

\_\_\_\_\_ form positively charged cations based on group number.

Answer 29

Metals

Question 30

Nonmetals form \_\_\_\_\_\_charged anions based on the number of electrons needed to achieve an octet.

Answer 30

negatively

Question 31

\_\_\_\_\_\_ contain equivalents of ions from molecules that dissociate in solution. The strength of an electrolyte depends on its degree of dissociation or solvation.

Answer 31

Electrolytes

Question 32

\_\_\_\_\_\_\_\_\_ is a combination of two or more atoms held together by covalent bonds.

Answer 32

A molecule

Question 33

A _______ is a quantity of any substance (atoms, molecules, dollar bills, kittens—anything) equal to the number of particles that are found in 12 grams of carbon-12 ( ) 6C12 .

Answer 33

A mole

Question 34

The conversion from normality to molarity of a given solute is formula

Answer 34

Question 35

Fill in the missing items

Answer 35

Question 36

HCO3- Hydrogen carbonate or bicarbonate HSO4- Hydrogen sulfate or bisulfate H2PO4-:

Answer 36

Dihydrogen phosphate

Question 37

Fill in the missing items

Answer 37