Question

what mass of oxygen gas is required to make 28g of nitrogen monoxide 4NH3+5O2 --> 6H2O+4NO

Answer 1

answrr is 37g but I don't know how to get it PLEASE HELP

Answer 2

first you need to convert the mass you have to moles, n, because you always work in moles.

moles=mass/molar mass (1)

next you use the stoichiometric coefficients to build relationship, like this:
\[\frac{ n _{NO} }{ 4 }=\frac{ n _{O _{2}} }{ 5 } \]

once you find the moles of O2, convert back to mass using the same formula (1)

Answer 3

I didn't get it. I did 28g/30.006 = 0.933 moles of NO then times by 5 then divided by 4. Which gave me 1.16625. I then times by 15.999 and it gave me 18.7 not 37g

Answer 4

what am I doing wrong

Answer 5

the molar mass of O2 is 32 not 16, you're only taking one oxygen atom into account

Answer 6

Got it ! Thank you soooooo much! :)

Answer 7

no problem! always double check your molar masses and constants

Answer 8

yes. 0.933 x 5/4 which gave me 1.16 then that times 2(15.999) gave me 37 g :)

Answer 9

when doing ratio for example 2NO-->5O2 would it be 2:5 or 2:10 ?

Answer 10

2 to 5, because you always use the coefficients.

but make sure to use the correct molar mass, molar mass of O2 is that of 2 oxygen atoms, people always forget that.

Answer 11

yeah! okay thank you so much you helped alot ! :)

Answer 12

no problem at allll, glad i could !