Dissolving calcium carbonate in hydrochloric acid produces aqueous calcium chloride, carbon dioxide, and water. CaCO3(s) + 2HCl(aq) → CaCl2(aq) + CO2(g) + H2O(l)

What mass of CO2 is produced by the reaction of 9.58 g CaCO3?
If 67.1g of CO2 is produced by this reaction, what mass of HCl must have reacted?
If 0.812 mol of HCl is used in this reaction, what mass of CaCO3 would be consumed? What mass of CO2 would be produced?

i'm pretty sure its b i might be wrong though!

hydrocarbons are organic compounds that contain only hydrogens and carbons. they can be saturated (those which contain only carbon-carbon single bonds) or unsaturated (those which contain carbon-carbon double or triple bonds) in nature. hydrocarbons can undergo several reactions like substitution, elimination etc.  

on substituting one or more hydrogen atoms in hydrocarbon it results in the formation of haloalkane. as the halogen atoms are large compared to the carbon and hydrogen atoms, due to which the molecular weight increases and the bond become polar because of presence electronegative halogen atom and results in the increase in boiling point of the haloalkane.

thus, the correct option is (b) that is the boiling point of the new compound increases on substituting a hydrogen atom with a halogen in a hydrocarbon.