Chapter 7

Question 1

def. Any part of a system that is uniform in composition and in properties, making it visually
distinct from the rest of the system

Answer 1

Phase

Question 2

def. Refers to an individual substance and all the particles of that substance

Answer 2

Chemical species

Question 3

def. A substance made up of only one chemical species, having only one type of particle
▪ Cannot be separated by physical means like filtration or distillation (i.e. without
breaking chemical bonds

Answer 3

Pure substance

Question 4

Can a pure substance have multiple phases?

Answer 4

Yes

Question 5

def. A substance made up of multiple chemical species, having more than one type of
particle
▪ Can be separated by physical means

Answer 5

Mixture

Question 6

def. The simplest pure substance, made up of either:
▪ Individual, identical atoms (He, O, C, etc.)
▪ * – Molecules of identical atoms (homonuclear molecules – H2, O2, etc.)

Answer 6

element

Question 7

def. o Made up of more than one element
o Can be made up of:
▪ Molecules (H2O)  covalent compounds
▪ Ion pairs (NaCl)  ionic compounds

Answer 7

compound

Question 8

def. Describes a system made up of only one phase

▪ All parts of the system contain the same substances in the same proportions

Answer 8

homogeneous

Question 9

def. Describes a system made up of more than one phase
▪ Different parts of the system contain either different substances or different
proportions

Answer 9

heterogeneous

Question 10

def. A type of homogeneous mixture, having multiple chemical species in a single phase,
where one or more substances dissolve into another

Answer 10

solution

Question 11

def. The part of the solution that exists in the smaller quantity – the minor component
▪ The part that is dissolving

Answer 11

solute

Question 12

def. The part of the solution that exists in the greater quantity – the major component
▪ What the solute dissolves into

Answer 12

solvent

Question 13

def. A type of heterogeneous mixture, containing multiple chemical species in multiple
phases, specifically insoluble solid particles that are large enough to settle out

Answer 13

suspension

Question 14

def. A type of heterogeneous mixture, having microscopic (1 nm to 1000 nm) dispersed
insoluble particles suspended throughout another substance

Answer 14

colloid

Question 15

def. A solution composed of a solute dissolved in water

Answer 15

aqueous solution

Question 16

How are aqueous solutions represented in chemical equations?

Answer 16

(aq)

Question 17

def. The number of moles of a substance contained in one litre of solution
▪ Expressed as mol/L or M

Answer 17

Molarity/ molar concentration

Question 18

def. Describes the maximum amount of solute that will dissolve in a given amount of solvent
at a particular temperature
▪ Most often expressed as mass per unit of volume (g/L or g/100 mL)

Answer 18

solubility

Question 19

def. Describes a solute that dissolves very poorly in a solvent, displaying low solubility
▪ Commonly defined as a solute whose molar solubility is less than 0.1 mol/L at
25 °C

Answer 19

insoluble

Question 20

def. Describes a solute that dissolves well in a solvent
▪ Commonly defined as a solute whose molar solubility is greater than 0.1 mol/L
at 25 °C

Answer 20

soluble

Question 21

def. The property of substances to mix and dissolve into each other in any proportion

Answer 21

miscibility

Question 22

def. Refers to substances that aren’t soluble and that do not mix in any proportion
▪ Water and oil do not dissolve into each other, producing two separate phases

Answer 22

Immiscible

Question 23

def. Refers to substances that are mutually soluble, that will mix in any proportion
▪ Alcohol and water dissolve into each other, producing a single phase

Answer 23

Miscible

Question 24

When does a precipitate form?

Answer 24

If the the reaction product is insoluble (low solubility)

Question 25

def. A solution into which solute can still dissolve, as the solute has not yet reached the maximum concentration for that solvent at that temperature

Answer 25

Unsaturated solution

Question 26

def. A solution into which no more solute can dissolve, as the solute has reached the maximum concentration for that solvent at that temperature

Answer 26

Saturated solution

Question 27

def. A solution that contains more dissolved solute than the solvent can at that temperature under normal circumstances

Answer 27

supersaturated solution

Question 28

def. Describes a material’s tendency to repel water or to not mix with it

Answer 28

hydrophobic

Question 29

def. Describes a material’s tendency to attract water or to mix with it

Answer 29

Hydrophilic

Question 30

what three things must occur for a solute to dissolve?

Answer 30

1. The solute’s particles must separate from one another 2. The solvent’s particles must separate from one another 3. The solute and solvent particles must mix together and attract each other

Question 31

what happens when particles separate?

Answer 31

ionic solutes must overcome the electrostatic attraction of their ionic bonds, covalent solutes must overcome the intermolecular forces holding them together

Question 32

In order for the solute’s particles to mix with those of the solvent there must be ....

Answer 32

enough space between the solvent’s particles

Question 33

If the forces holding the solute’s particles together are stronger than the other two, then the solute________ is the most favourable outcome, and the solute _________

Answer 33

staying together, the solute won't dissolve

Question 34

if the intermolecular forces within the solvent are stronger than the other two, then the solvent’s particles ___________ is the most favourable outcome, and the solute _______

Answer 34

staying together, the solute won't dissolve

Question 35

If the forces that attract the solute’s particles to the solvent’s particles are stronger than the other two, then the two _______ together is the most favourable outcome and the solute _______

Answer 35

Mixing together, solute will dissolve

Question 36

A solute will only dissolve if the attractive forces between its particles and those of the solvent are _________ than the forces within the solute or the solvent

Answer 36

as strong or stronger

Question 37

def. The attractive force that exists between the partial positive charge of one polar molecule and the partial negative charge of another

Answer 37

dipole-dipole

Question 38

def. An electrostatic attraction that forms between the partially positive hydrogen in a highly polarized bond (usually H–N, H–O and H–F) and the negative lone pair on a nearby atom

Answer 38

hydrogen bond

Question 39

def. A weakly attractive force that forms when nonpolar molecules gain temporary dipole moments

Answer 39

london dispersion forcesq

Question 40

def. The separation of the component ions of an ionic compound when it dissolves in water

Answer 40

Dissociation

Question 41

def. A molecule that has an overall, or net dipole moment, because of its bond polarities and its molecular geometry

Answer 41

Polar molecule

Question 42

def. An attractive force that forms between the partial charge of a molecular dipole moment and an oppositely charged ion

Answer 42

ion-dipole force

Question 43

Polar solvents dissolve ionic and polar solutes because of either favourable _________ forces, favourable ________ bonding or favourable ________ forces

Answer 43

ion-dipole, hydrogen, dipole-dipole

Question 44

Nonpolar covalent solutes are only soluble in nonpolar covalent solvents because of favourable __________ forces

Answer 44

London dispersion forces

Question 45

Why do soaps help clean?

Answer 45

One side is hydrophilic (polar) and the other is hydrophobic (non-polar)

Question 46

def. A solution of relatively high concentration | ▪ A large amount of solute dissolved in the solvent

Answer 46

concentrated

Question 47

def. A solution of relatively low concentration | ▪ A very small amount of solute dissolved in the solvent

Answer 47

dilute

Question 48

whats the formula for finding final concentration?

Answer 48

[𝐟𝐢𝐧𝐚𝐥] = 𝐦𝐨𝐥𝐞𝐬𝐭𝐨𝐭𝐚𝐥/ 𝐯𝐨𝐥𝐮𝐦𝐞𝐭𝐨𝐭𝐚l

Question 49

def. The process of solvent molecules surrounding solute ions or molecules, in order to form favourable ion-dipole or intermolecular forces

Answer 49

Solvation

Question 50

def. Refers to the process of solvation when the solvent is water

Answer 50

hydration

Question 51

def. An equation similar to a chemical equation that shows the separation of an ionic compound into its component ions

Answer 51

Dissociation equation

Question 52

what do we use to describe the dissocation of ionic solutes?

Answer 52

dissociation equations

Question 53

def. An equation similar to a chemical equation that shows the breakup of a neutral molecule into charged pieces

Answer 53

ionization equation

Question 54

what's the difference between an ionization equation and a dissociation equation?

Answer 54

Dissociation equations start with ionic compounds, ionization equations start with covalent compounds

Question 55

the following is an example of what kind of equation? NaCl(aq) --> Na+ (aq) + Cl– (aq)

Answer 55

Dissociation

Question 56

``` the following is an example of what kind of equation? HCl(aq) --> H + (aq) + Cl– (aq) ```

Answer 56

Ionization equation

Question 57

_________ equations represent the separation of ionic compounds into ions that already exist, while _________ equations represent covalent compounds that breakup to form ions

Answer 57

Dissociation, ionization

Question 58

def. A quantitative measure of a solution’s ability to conduct electricity, thanks to its ionic content

Answer 58

conductivity

Question 59

___________ though most often referring to the flow of electrons, actually refers to a flow of any charged particles, including ions

Answer 59

electrical current

Question 60

def. A substance that only partially dissociates or ionizes in solution, producing a solution that conducts electricity, but only weakly

Answer 60

weak electrolyte

Question 61

def. A substance that completely, or almost completely, dissociates or ionizes in solution, producing a solution that conducts electricity very well

Answer 61

strong electrolyte

Question 62

def. A substance that dissolves, but that doesn’t dissociate or ionize, producing a solution that does not conduct electricity

Answer 62

non-electrolyte

Question 63

what two mechanisms produce conductive solutions?

Answer 63

Ionization, dissociation

Question 64

def. A common laboratory technique that allows you to determine the unknown concentration of a solution, by reacting it with a second solution whose concentration you do know

Answer 64

titration

Question 65

def. The solution whose concentration you know | ▪ Ends in “t” because you put it in the tube rather than in the flask

Answer 65

titrant

Question 66

def. The solution whose concentration you want to figure out | ▪ Ends in “d” because you don’t know its concentration and want to determine it

Answer 66

titrand

Question 67

def. A solution whose concentration you know relatively precisely

Answer 67

standardized solution

Question 68

def. An exothermic double replacement reaction between an acid and a base that always produces a salt and water

Answer 68

neutralization

Question 69

what is this an example of? | HX(aq) + MOH(aq) --> MX(aq) + H2O(l) + heat

Answer 69

neutralization

Question 70

What four things do we need to complete titration calculations?

Answer 70

- stoichiometric mole ratio between the acid and the base - volume of the titrand - concentration of the titrant - the volume of your titrant

Question 71

What is the purpose of a titration?

Answer 71

to figure out how much titrant is needed to neutralise the titrand

Question 72

def. A piece of laboratory equipment designed for very accurate (four significant figures) measuring and dispensing of a specific volume of solution

Answer 72

volumetric pipette

Question 73

def. A piece of laboratory equipment designed for very accurate (four significant figures) measuring and dispensing of a variable volume of solution

Answer 73

burette

Question 74

def. The point in a titration at which the ratio of the moles of titrant to those of titrand is identical to the ratio of their coefficients in the balanced chemical equation

Answer 74

equivalence point

Question 75

At the equivalence point, the contents of the flask have pH = ?

Answer 75

7

Question 76

def. A group of chemical compounds that change colour based on pH, when added in small amounts to a solution

Answer 76

pH indicators

Question 77

def. The point in a titration at which the pH indicator changes colour, signaling the titration’s end and the titrant volume you record

Answer 77

endpoint