Steps to calculate reacting masses

Question 1

1st Step

CaCo₃ –> CaO + CO₂
CaCo₃ = 23.4 g

Answer 1

Identify 2 substances (Which two substances you need and which ones you don’t)
CaCo₃ —-> CO₂
CaCo₃ = 23.4 g

Question 2

2nd Step

CaCo₃ —-> CO₂
CaCo₃ = 23.4 g

Answer 2

M (mass)
Mᵣ (Relative molecular mass)
n (number of moles)
M/Mᵣ=n

CaCo₃ —-> CO₂
M = 23.4g M=
Mᵣ = 100 Mᵣ=
n = 0.234 n=

Question 3

3rd Step

Answer 3

Calculate n. of moles + consider ratios
(1 : 1 or 2 : 1)

CaCo₃ —-> CO₂
M = 23.4g M=
Mᵣ = 100 Mᵣ=
n = 0.234 n= 0.234

1 : 1

Question 4

4th Step

Answer 4

Calculate the missing mass

CaCo₃ —-> CO₂
M = 23.4g M=10.296g
Mᵣ = 100 Mᵣ= 44
n = 0.234 n= 0.234

But round it to 3 sig figs because mas of CaCo₃ is in 3 sig fig. So M for CO₂ = 10.3