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chemistry

this is supposed to be a really straight forward question but I don't get it can some one please help?
This question is about the reaction between hydrogen sulfide (H2S) and oxygen.
The equation for the reaction is:
2H2S(g) + 3O2(g) 2H2O(g) + 2SO2(g)
Calculate the volume of oxygen required to react with 50 cm3 of hydrogen sulfide?
Original post by iris kh
this is supposed to be a really straight forward question but I don't get it can some one please help?
This question is about the reaction between hydrogen sulfide (H2S) and oxygen.
The equation for the reaction is:
2H2S(g) + 3O2(g) 2H2O(g) + 2SO2(g)
Calculate the volume of oxygen required to react with 50 cm3 of hydrogen sulfide?

Hi
If we assume all the gases are ideal, in constant temperature and pressure the amount of gas is directly proportional to the volume of the gas ( You can derive this result easily from the ideal gas equation or it's simply the Avogadro's Law)
And we can see that H2S and O2 react in 2:3 ratio (from the reaction equation) so that if we have 50cm3 of H2S
we need (50/2)*3 cm3 of O2 which is 75 cm3 to complete the reaction
hope this helps
Reply 2
Hi, not sure if your doing gcse or a-level

but try here it shows you how to do it
https://science-revision.co.uk/moles_and_gases.html

if your doing a-level need to use the ideal gas equation but method similar to the one of the gcse page, just calculate no of moles from the equation, calculate the number of moles in 50ml of H2S and multiply by 1.5 to get moles of oxygen
Original post by eaglespirit
Hi
If we assume all the gases are ideal, in constant temperature and pressure the amount of gas is directly proportional to the volume of the gas ( You can derive this result easily from the ideal gas equation or it's simply the Avogadro's Law)
And we can see that H2S and O2 react in 2:3 ratio (from the reaction equation) so that if we have 50cm3 of H2S
we need (50/2)*3 cm3 of O2 which is 75 cm3 to complete the reaction
hope this helps


that's what i got but apparently the answer is 70cm3 but i don't know how you do it

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