Following will be chemical reaction:
For limiting reagent,
4 g H, reacts with = 32 g O2
3 g H2 will react with \( = \frac{32\times 3}{4} = 24 \ g \ O_2\)
But according to problem, we have 30 g 02. viz O2 is in excess,
So, the limiting reagent for this reaction is ydrogen.
4 g H2 form = 36 g H2O
3 g H2 will produce = \(\frac{36\times 3}{4}\)
= 27 g H2O