What mass of water is produced when 8.0g of hydrogen reacts with excess oxygen?
[H = 1, O = 16]
36.0g
8.0g
72.0g
16.0g
Explanation
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Discussions (29)

The equation in the answer is not correct. The questions says oxygen is in excess.
So the equation is
4H2 + 2O2 = 4H2O
8g 4g 72g
find the Relative Formula Mass of water = (1 x 2 + 16) x 4 = 72g

The molar mass of 2H2 is 4g
Now, if this 4g of Hydrogen(H) reacts with excess oxygen, it will produce 36g of Water.
The question is now asking"What mass of water is produced when 8.0g of Hydrogen reacts with excess Oxygen?"
In essence, If 4g gives 36g. What will 8g give?
And that will be:
4g--------->36g
8g--------->?g
By cross multiplying, We should have:
4*?g=36g*8
Divide both sides by 4g to make ?g the subject of the formula, since it it the the mass of what we are looking for.
36*8=288
288/4=72g
Therefore, the mass of water produced when Hydrogen reacts with excesss oxygen is 72g.

Broo I now get
2H2+O2----->2H20
2mol of H = 2 mole of water
Mole of H =mass/molarmass
H=8/2. (H=1=> H2-->2)
H =4
4mol of H = 4 mol of water
= 4mol of water=mass/molarmass

4=mass/18. | (H20->18)=
(Cross multiply) | 2+16=18
4 x 18 =mass
72g=mass of water
Yur welcome ๐๐๐



