If you need to produce 9.75 moles of iron(III) oxide (Fe2O3), how many moles of iron will be required? *

Thus 9.75 moles of iron will be required.

Explanation:

The balanced chemical reaction is:

According to stoichiometry :

2 moles of are produced by= 2 moles of

Thus 9.75 moles of are produced by=  of

Thus 9.75 moles of iron will be required.

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.

i believe the answer is 5,000