What is the total number of moles present in a 52.0 gram sample of #NaN_3#?

Gram-formula mass = 65.0 grams/mole

1 Answer
Nov 15, 2016

Answer:

#"0.800 moles"#

Explanation:

The formula for calculating moles given the mass and a compound is:

#n = m/M#

#n# = moles
#m# = mass in grams #("g")#
#M# = molar mass #("g/mol")#

The molar mass is the sum of all the atomic masses in the compound.

#"Na" = "22.99 g/mol"#
#"N" = "14.01 g/mol" xx 3 -># (there are #3# #"N"# atoms)

Add them up and you get #"65.02 g/mol"#

#n = m/M#

# = (52.0 cancel("g"))/(65.02 cancel("g")/"mol")#

#= "0.799753921 moles"#

#= "0.800 moles " -># (rounded to three sig figs)

Therefore, there are #0.800# moles in 52.0g of #"NaN"_3#.

I hope this made sense :)