Question

if 8 mL of uncombined O2 remain after exploding O2 with 4 mL of hydrogen the number of mL of O2 originally were​

Answer 1

Answer : The volume of $O_2$ originally were, 10 ml

Explanation :

The balanced chemical reaction will be:

$2H_2+O_2\rightarrow 2H_2O$

From the balanced chemical reaction, we conclude that

As, 2 ml of hydrogen react with 1 ml of oxygen

So, 4 ml of hydrogen react with $\frac{4}{2}=2ml$ of oxygen

The volume of combined oxygen = 2 ml

The volume of uncombined oxygen = 8 ml

Thus, the original volume of oxygen = 8 ml + 2 ml = 10 ml

Therefor, the volume of $O_2$ originally were, 10 ml

Answer 2

Answer:

10ml is the original volume of O2

Explanation:

see explanation in attachment ⬆️