If you start with 30 moles of O2, how many moles of SiO2 can you make?

30moles of SiO₂

Explanation:

Given parameters:

Number of moles of O₂  = 30moles

Unknown:

Number of moles of SiO₂  = ?

Solution:

To solve this problem, we need to write the reaction expression:

       Si +  O₂  →  SiO₂  

The reaction is balanced;

      1 mole of O₂ will produce 1 mole of SiO₂

     30mole of O₂ will produce 30moles of SiO₂

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.