Numeracy Definitions

Question 1

Define Concentration

Answer 1

Conc is amount of Solute dissolved in an Amount of Solution

Question 2

Define Molar Concentration (Molarity)

Answer 2

Num of Moles of Solute Dissolved in Volume of Solution (Litres)

Question 3

Molarity Equation

Answer 3

num of n / Volume (L)

Question 4

Simple Molarity - Steps to Solve

Answer 4

1. Molecular Mass of Solute?
2. How many Moles in Solute?
3. Solvent in Litres
4. Divide answers to Step 2 by Answer to Step 3
5. Fix Decimal Place (2)

Question 5

Percentage Weight per Weight (%w/w)

Answer 5

Amount of Active ingredient measured in mg present in 100mg of Solid or Semi Solid

Question 6

Percentage Volume by Volume (%v/v)

Answer 6

Amount of Active Ingredient measured in mL present in 100mL of Solution

Question 7

Concentration: X in Y or X:Y

Answer 7

• Concentration defined as e.g. 1:5000 means 1g in 5000mL
• Variation of %w/v definition

Question 8

Steps to Solve for %w/w

Answer 8

1. Define %w/w
2. Inspect data = do any units need to be changed
3. Do any values need scaling to bring them to correct conc based on (1)
4. Ensure answer in correct unit + decimal place

Question 9

Step to Solve %v/v

Answer 9

1. Define %v/v
2. Inspect data - Do any of the units need changing
3. Do any values need scaling to bring them to correct conc based on (1)
4. Ensure data in Correct Units + Decimal Place

Question 10

Percentage Weight by Volume (%w/v)

Answer 10

Amount of Active Ingredient measured in g present in 100mL of Solution

Question 11

Steps to Solve %w/v

Answer 11

1. Define %w/v
2. Inspect Data - Change any units which need changing
3. Do any values need scaling to bring to correct concentration for (1)
4. Ensure Correct Units + Decimal Place

Question 12

Single Strength

Answer 12

1 in 40 Dilution

Question 13

Double Strength

Answer 13

1 in 20 Dilution