Chapter 3 - Solutions

Question 1

What is the formula to find the concentration of a solution? Explain what each part means.

Answer 1

C = solute / solution.  ( / = over)
C = concentration (g/L)
solute = mass or volume of solute (g or L)
solution = mass or volume of solution (g or L)

Question 2

How do you calculate a concentration in ppm?

Answer 2

1 g
———
1 000 000 mL

Question 3

How do you calculate the concentration in % in all forms?

Answer 3

1 g
——-
100 mL

1 mL
——-
100 mL

1 g
——-
100 g

Question 4

What is dilution?

Answer 4

Adding solvent to an existing solution. This increases the volume and decreases the concentration.

Question 5

What’s the formula for dilution?

Answer 5

C1 x V1 = C2 x V2

Question 6

What are the units for the formula of dilution?

Answer 6

C1 + C2 = g/L , % , ppm

V1 + V2 = mL , L

Question 7

What are electrolytes?

Answer 7

Substances that break down into ions when dissolved in water (allows to conduct electricity)

Question 8

How do you recognize an electrolyte that is an acid?

What’s the exception?

Answer 8

Chemical formula starts with H and ends with a nonmetal.

*expection: CH3COOH

Question 9

How do you recognize an electrolyte that is a base?

What’s the exception?

Answer 9

Chemical formula starts with a metal and ends in OH.

*exception: NH3

Question 10

How do you recognize an electrolyte that is a salt?

Answer 10

Chemical formula that starts with a metal and ends with a nonmetal.

Question 11

What is the pH scale of an acidic solution?

Answer 11

Anything below 7

Question 12

What is the pH scale of a neutral solution?

Answer 12

7

Question 13

What is the pH scale of a basic solution?

Answer 13

Anything over 7

Question 14

What is a pH indicator?

Answer 14

A substance that changes colour for specific pH ranges

Question 15

What is a turning point?

Answer 15

The zone when the indicator changes from its initial to final colour