How many grams are there in #7.50 x 10^23# molecules of #H_2SO_4#?

2 Answers
May 14, 2018

Answer:

Well, how many grams in #6.022xx10^23# #"sulfuric acid molecules"#?

Explanation:

It is a fact that such a quantity has a mass of #98.08*g#. Why? Because #6.022xx10^23# particles SPECIFIES a molar quantity. And we know (or can calculate) that sulfuric acid has a molar mass of #98.08*g#...

And so we take the quotient....

#(7.5xx10^23*"sulfuric acid particles")/(6.022xx10^23*"sulfuric acid particles"*mol^-1)xx98.08*g*mol^-1=122*g#...

May 14, 2018

Answer:

#122.5g#

Explanation:

  • 1st, we need to convert #7.50#x#10^23#molecules into moles

#7.50#x#10^23#molecules x #(1mol)/(6.02x10^23)# =#1.25mol#

  • Now we convert #1.25mol# to grams #(g)#

#1.25cancel(mol# x #(98g)/(1cancel(mol)# = #122.5g#

  • Note, when converting to grams, its gram formula mass / #1mol#. The formula mass is all the element's masses added together

#H_2# = #1g# x #2# = #2g#

#S# = #32g#

#O_4# = #16g# x #4# = #64g#

#2g# + #32g# + #64g# = #(98g)/(1mol)#