Unit 4 - Solution and Solubility

Question 1

What is a solution?

Answer 1

homogeneous (only one visible part) mixture of two or more substances

Question 2

What is a heterogenous mixture?

Answer 2

Containing 2 or more visible parts

Question 3

What is miscible and immiscible?

Answer 3

When a liquid can dissolve with each other and when a liquid can’t mix/dissolve with each other

Question 4

Polarities and solutions (trend)

Answer 4

• Solutions with similar polarities are often miscible and solutions with opposite polarities are immiscible (like dissolves like)

Question 5

What is dissociation?

Answer 5

When ionic solids are mixed with water, polar molecules pull the negative ions apart from the crystal.
- As ions leave the crystal, they are surrounded by
water in a process called hydration (negative charges will go to the positive charge, and vise versa)

Question 6

What are the components of a solution?

Answer 6

Solute and the solvent

Question 7

What is the concentration of a solution?

Answer 7

The ratio of the quantity of solute to the quantity of solvent

Question 8

What is alloy and amalgam?

Answer 8

• A solution of 2 or more metals
• Alloys of mercury

Question 9

What is the solubility trend?

Answer 9

• Saturated solution: contains max quantity of solute
• Unsaturated solution: contains less than max quantity (dissolves more solute)
• Supersaturated solutions: contains more than the max amount of solute

Question 10

What are the 4 factors affecting solubility?

Answer 10

1. Increase temp = increase in kinetic energy between particles –> causing more collisions between solute and solvent particles
2. Agitating the solution (like stirring), increase the interaction between solute and solvent particles
3. Decreasing particle size (grinding the solute), increasing surface area of solute and allowing more interactions
4. Increasing solubility = increase rate of dissolving

Question 11

Difference between solubility of gases and solids?

Answer 11

• Solubility of gases decreases as the temperature increases
• Solubility of gas in liquid increases as the pressure of the gas increases
  (As the solvent vapor pressure increases with the additional kinetic energy the entire system becomes volatile, because you have additional kinetic energy. This prevents more gas from dissolving into the system.)

Question 12

What are the trends of solubility in gases?

Answer 12

1. Thermal pollution decreases solubility of oxygen in water
2. Cold water warming up to room temp, solubility of gases reduces
3. Open a bottle of pop decreases pressure, solubility of CO2 decreases and reduce (gas is released)

Question 13

What is a stock solution?

Answer 13

Concentrated solution that is used to prepare dilute solutions for actual use

Question 14

What is a standard solution?

Answer 14

Solution of a known concentration, where it is used due to its low uncertainty

Question 15

What is a dilution?

Answer 15

Process of reducing the concentration of a solution by adding more solvent

Question 16

What is filtrate?

Answer 16

The clear liquid (solvent and any dissolved substances) collected after a mixture is filtered to remove any
solid components is called the filtrate

Question 17

What is an oxyanions?

Answer 17

Polyatomic anion that contains oxygen

Question 18

What are the rules of oxyanions? –> not acids

Answer 18

Prefixes:
Per- = 1 more oxygen atom
-ate = no changes
-ite = 1 less oxygen atom
Hypo__ite = 2 less oxygen atoms

Question 19

What are acid nomenclature? –> acid (adding hydrogen)

Answer 19

1. Acids without oxygen have form hydro__ic acid (aqueous)
   - they are filled with the elements or polyatomic ion name following hydrogen in the formula
2. Acids with oxygen end with -ic (higher, ex Cu^+2) or -ous (lower version, ex Cu^+1) acid
   - -ate oxyanions become -ic acids and -ite oxyanions become -ous acids

Question 20

What is arrhenius theory?

Answer 20

Proposed that acids and bases can be classified according to their chemical formulas and how they dissociate in water
1. Arrhenius base - substance that dissolves in water –> creating a cation and OH
2. Arrhenius acid - ionizes to produce hydronium ions in water –> into hydrogen (no H2, just H) or H3O

• DOESN’T APPLY TO AMMONIA

Question 21

What is the difference between ionization vs. dissociation?

Answer 21

Dissociation - occurs when water molecules pull apart the positive and negative ions of an ionic compound
Ionization - occurs when ions form in solution from neutral molecule

Question 22

What is acid-base strength?

Answer 22

In a solution of strong acid, no HA remains (fully ionizes to H3O+ and A–)
In a solution of a weak acid, very little ionization occurs and most of it remains in the form HA

(HA is the compound that is being added to water)

+These all depend on their degree of dissociation in solution

Question 23

What is titration?

Answer 23

An analytical procedure used to determine the concentration of a solution

Question 24

What are the key terms in titration?

Answer 24

1. Equivalence point - when the compound neutralize completely)
2. End point - when the indicator change colour

Question 25

What is standardizing in titrants?

Answer 25

Determining the precise concentration of the titrant before performing

Question 26

What is a primary standard?

Answer 26

A chemical that is highly pure and chemically stable that is used to determine the precise concentration of acids or bases

Question 27

What is qualitative analysis and quantitative analysis?

Answer 27

- Qualitative analysis involves detecting or identifying a substance - Quantitative analysis involves measuring a specific quantity or characteristic of a substance

Question 28

What is concentration?

Answer 28

The amount of substance in a solution (amount of salt in blood)

Question 29

What is solubility?

Answer 29

It is the maximum mass of solute that can be dissolved per 100 g of water at a given temperature and pressure

Question 30

What are flame tests used for?

Answer 30

It is harder to identify the presence of alkali metals, so a flame test is used, where if these metals are present, it turns into a certain colour.