Question

how many grams of CO2 evolved from a 1.205g sample that is 36% MgCO3 and 44% K2CO3 by mass?

Answer 1

Mass of CO₂ evolved : 0.108 g

Further explanation

Given

1.205g sample, 36% MgCO3 and 44% K2CO3

Required

mass of CO2

Solution

• mass of MgCO₃ :

0.36 x 1.205 g=0.4338 g

mass C in MgCO₃(MW MgCO₃=84 g/mol,  Ar C = 12/gmol)

= (12/84) x 0.4338

= 0.062 g

• mass of K₂CO₃ :

0.44 x 1.205 g = 0.5302 g

Mass C in K₂CO₃(MW=138 g/mol) :

= (12/138) x 0.5302

= 0.046 g

Total mass Of CO₂ :

= 0.062 + 0.046

= 0.108 g