Chemical Calculations

Question 1

What is the formula for calculating moles from mass?

Answer 1

Moles = Mass (g) ÷ Molar Mass (g/mol)

Question 2

What is the formula for calculating mass from moles?

Answer 2

Mass = Moles × Molar Mass

Question 3

What is Avogadro’s number?

Answer 3

6.022 × 10²³ particles per mole

Question 4

How do you calculate the number of particles in a given number of moles?

Answer 4

Particles = Moles × Avogadro’s number

Question 5

What is the formula for percentage yield?

Answer 5

Yield = (Actual Yield ÷ Theoretical Yield) × 100

Question 6

Q: How do you convert cm³ to dm³ and m³?

Answer 6

1000 cm³ = 1 dm³; 1000 dm³ = 1 m³

Question 7

What is the formula for percentage yield?

Answer 7

Yield = (Actual Yield ÷ Theoretical Yield) × 100

Question 8

How do you calculate the concentration of a solution?

Answer 8

Concentration (mol/dm³) = Moles ÷ Volume (dm³)

Question 9

How do you calculate moles in a solution?

Answer 9

Moles = Concentration × Volume (in dm³)

Question 10

What is a limiting reagent?

Answer 10

The reactant that is used up first and limits the amount of product formed.