What is the mass of #2.30 x 10^24# formula units of magnesium chloride?

1 Answer
Nov 20, 2016

Answer:

#"Mass"# #~=# #380*g#

Explanation:

Here we use #N_A#, #"Avogadro's number"# as our counting number, where #N_A=6.022xx10^23*mol^-1#.

#"Avogadro's number"# of #MgCl_2# formula units have a mass of #95.21*g#. Alternatively we say the molar mass of #MgCl_2# is #95.21*g*mol^-1#.

So we work out the quotient,

#(2.30xx10^24)/(6.022xx10^23*mol^-1)xx95.21*g*mol^-1~=4xx95.21*g#