Consider the following reaction
CO2(g) + H2(g) — COG) + H2011)
What is being oxidized?
carbon
carbon dioxide
oxygen
hydrogen
Dedio

H2

Explanation:

CO2 + H2 → CO + H2O

↓ (-2). 0. (+2 )(-2). (+1)(-2)

↓ ·2 (+2)

+4 (-4)

Write down the oxidation number under each element, each molecule should equal 0 unless there is a charge shown.

Oxygen, always has an oxidation number of -2 unless in a peroxide.

Hydrogen, is -1 with metals,+1 with non-metals. Hydrogen loves non-metals!

H2 is zero because any standalone element has an oxidation number of zero

What is being oxidized? Whatever is being oxidized, loses electrons and becomes more positive, it will be a whole molecule, not just an element. In this case, the H in H2 goes from 0 to (+1) so it is the oxidized molecule.

the ideal gas law equation is as follows

pv = nrt

where p - pressure

v - volume

n - number of moles

r - universal gas constant

t - temperature

so if the pressure, volume and temperature are already known

we are left with n and r

since r is the universal gas constant that has a known fixed value then r too is known

so we are left with 'n'

once we know temperature volume and pressure

we can find the number of moles of gas present using the ideal gas law equation

this is not my own answer, this is an answer for the same question by the user blahblahmali. i do not claim ownership of this account.