Calculate grams according to equation

[omni]

i got this equation:2c2h2+5o2->4co2+2h2o

how i Calculate how many grams of C2H2 and how many mol of O2 are Necessary to get 0.005 mol Gas CO2?

and tell me if i Right: to Calculate the mass ( in gr) of 100 Molecules SO2.
I did like this: the mass of SO2 is 64 gr/mol so 100 Molecules will have this mass:100*64? but i not sure i need to find the mass in gr

thanks.

 

[Borek]

Don't ignore capital letters in formulas.

Try to learn how to read reaction equation.

Remember - if you know number of moles, you can easily calculate mass and vice versa.

For mass of molecules you can either use amu, or take into account Avogadro's number.

Finally: post all homework, or homework type questions in appropriate forum, that is somewhere here.