Lithium and nitrogen react in a combination reaction to produce lithium nitride: 6li (s) + n2 (g) → 2li3n (s) in a particular experiment, 4.00-g samples of each reagent are reacted. the theoretical yield of lithium nitride is g.

6.69 g.

Make sure the chemical equation is balanced:

Assuming that one mole of N₂ is consumed. How many grams of each reactant will that take? Refer to a periodic table for data on atomic mass.

4.00 grams of each reactant are available. How many moles of N₂ can they consume?

However, only 0.09606 moles of the reaction is possible, since Li would have ran out before all 4.00 grams of N₂ are used up.

Each mole of the reaction makes 2 moles of Li₃N. 0.09606 moles of the reaction will produce 0.09606 × 2 × (3 × 6.94 + 14.01) = 6.69 grams of Li₃N.

the answer is d. 74.02

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.