Exam 2: Solutions

Question 1

Chemical reactions that take place in _____ are the most common and most important

Answer 1

water

Question 2

Define solution

Answer 2

homogeneous mixture of two or more substances

Question 4

Define solvent

Answer 4

major component of the mixture (usually water)

Question 5

Define solute

Answer 5

minority component of the mixture

Question 6

The solubility of one substance into another depends on what?

Answer 6

• intermolecular forces (like dissolves like, between solvent and solute particles, between individual solvent particles, between individual solute particles)
• tendency to mix (based on entropy)

Question 7

Define entropy

Answer 7

a measurement of energy randomization or energy dispersal in a system

Question 8

Why is agitating a mixture effective?

Answer 8

the more the solute interacts, the faster it will dissolve in the solvent

Question 9

What does it mean if a solution is saturated?

Answer 9

it means the solvent is holding the maximum amount of solute dissolved (no more solute will dissolve if added)

Question 10

What does it mean if a solution is unsaturated?

Answer 10

it means the solvent is holding less than the maximum amount of solute dissolved (more solute will dissolve if added)

Question 11

Heat will ______ solubility

Answer 11

increase

Question 12

What does it mean if a solution is supersaturated?

Answer 12

it means the solvent is holding more than the maximum amount of solute dissolved (usually unstable)

Question 13

How can you create a supersaturated solution?

Answer 13

when the saturation point of a solution is reached, heat it up and add more solute (when it cools it will stay dissolved)

Question 14

Kilo (k)

Answer 14

1000g (1 x 10^3g)

Question 15

deci (d)

Answer 15

0.1g (1 x 10^-1g)

Question 16

centi (c)

Answer 16

0.01g (1 x 10^-2g)

Question 17

milli (m)

Answer 17

0.001g (1 x 10^-3g)

Question 18

micro (fancy m)

Answer 18

0.000001g (1 x 10^-6g)

Question 19

nano (n)

Answer 19

0.000000001g (1 x 10^-9g)

IMPORTANT FOR POTENCY

Question 20

Define molecular weight

Answer 20

• the amount in chemistry (not mass)
• utilizes moles (goes from mass on a scale to a number to compare regardless of the atom)

Question 21

Define mole

Answer 21

• the standard number to compare regardless of atom

Question 22

Define density

Answer 22

the relationship between the mass of a sample and the volume it takes up)

Question 23

Diluted or concentrated are ways to describe the amount of _____ in a solution

Answer 23

solute

Question 24

What are the 3 expressions of concentration?

Answer 24

• molarity (mol/L)
• weight percent (mass/mass x 100%)
• volume percent (volume/volume x 100%)

Question 25

Defne molality

Answer 25

• solution concentration expressed in moles of solute/kg of solvent
• independent of temperature, but can change depending on the density of solvent

Question 26

weight percent (w/w)

Answer 26

• solution concentration expressed as a percentage of the solute mass in the mass of the solution
• useful when the solute is a solid (easy to weigh)
• 100g is the easiest assumption

Question 27

volume percent (v/v)

Answer 27

• solution concentration expressed as a percentage of the solute volume in the volume of the solution
• useful when the solute is a liquid
• 100mL is the easiest assumption