What is the percent of li in li3n ?

Li percentage in is 59.8%.

Explanation: The question asks to calculate the mass percentage of Li in .

The formula used for mass percentage of an element in a compound is:

mass percentage =

Atomic mass of Li is 6.94 and atomic mass of N is 14.0.

There are three Li in the given compound. So, the mass of Li in the compound is = 3(6.94) = 20.82

Mass of compound = 20.82 + 14.0 = 34.82

Mass percentage of Li =  = 59.8%

Hence, the percentage of Li in is 59.8%.

given:

mass of na = 115 g

excess cl2

to determine:

mass of nacl produced

explanation:

given reaction is-

2na(s) + cl2(g) → 2nacl(s)

since cl2 is in excess, na will be the limiting reagent

as per the reaction stoichiometry na: nacl = 1: 1

i.e. moles of na reacted = moles of nacl formed

now, # moles of na = mass of na/atomic mass

                                  = 115 g/23 g.mol-1 = 5 moles

therefore, moles of nacl = 5

molar mass of nacl = 58 g/mol

mass of nacl = 5 moles * 58 g.mol-1 = 290 g

ans: amount of nacl produced = 290 g