What is the molar mass (gram formula mass) for the compound sodium thiosulfate, #Na_2S_2O_3#?

1 Answer
Mar 15, 2018

Answer:

I get #158.13 \ "g/mol"#.

Explanation:

To calculate the molar mass of sodium thiosulfate, #Na_2S_2O_3#, we need to find all the molar masses of the elements, and add them together.

#Na# has a molar mass of #23 \ "g/mol"#. So, #Na_2# will have a molar mass of #23 \ "g/mol"*2=46 \ "g/mol"#.

#S# has a molar mass of #32.065 \ "g/mol"#. So, #S_2# will have a molar mass of #32.065 \ "g/mol"*2=64.13 \ "g/mol"#.

#O# has a molar mass of #16 \ "g/mol"#. Therefore, ozone, or #O_3#, will have a molar mass of #16 \ "g/mol"*3=48 \ "g/mol"#.

Adding all the molar mass together, we find that the molar mass of sodium thiosulfate #(Na_2S_2O_3)# is:

#46 \ "g/mol"+64.13 \ "g/mol"+48 \ "g/mol"#

#=158.13 \ "g/mol"#.