What is the volume ofCO2 measured at S.T.P which is involved on heating10.5g of NaHCO3

Heating NaHCO3 to what temperature? If to about 270 C or so it is

2NaHCO3 ==> CO2 + Na2CO3 + H2O

mols NaHCO3 = grams/molar mass
Using the coefficients in the balanced equation convert mols NaHCO3 to mols CO2.
Then 22.4L x ?mols = ? L at STP