I am struggling with this problem on gas stochiometry

Question

What volume in millilters of sulfur dioxide can be produced by the complete reaction of 3.82g of calcium sulfite with excess HCl(aq), when the final SO2 pressure is 827 torr at 44°C?

 

 

 

Answer 1

This is an example of stoichiomistry that involves a gas.  H₂SO₃ (like H₂CO₃) will decompose in water to produce a gas)  Your general outline to work these types of question is:

(1)  Write a balanced reaction

(2)  Determine the moles of the solid

(3)  Determine the moles of the gas

(4)  Use ideal gas law to determine the volume.

 

Reaction:  CaSO₃ (aq) +  2 HCl(aq)---->  H₂SO₃(aq)  +  CaCl₂ (aq)  ---->  H₂O(g)   +  SO₂ (g)  +  CaCl₂(g)

 

3.82 g CaSO₃  x   1mol/120.14 g  x  1 mol SO₂/1mol CaSO_{3 =}  0.0318 mole SO₂

 

827 torr x  1 atm/760torr  x  V  =  0.0318 mole SO₂ x 0.08206 Latm/mol K x (44+273 K)

                                          V = 0.76 L