Question

If you ever watch a shuttle launch, you will see what looks like a crazy amount of smoke at the take off. but if you get up closer to the launch pad afterwards, you will see a bunch of ice! the reason is because hydrogen gas is the fuel, and it is being combusted with oxygen gas to form water: 2h2 + o2 → 2h2o. we will learn later why ice forms here even though it is so warm. but for now, what would be the total mass in grams of water (ice) if you completely combusted 200.0 kilograms of hydrogen gas? note: all numbers located immediately after elemental symbols should be considered subscripts.

Answer 1

Answer:

1.788 × 10⁷ g

Explanation:

Let's consider the following balanced equation.

2 H₂ + O₂ → 2 H₂O

We can establish the following relations.

• The molar mass of H₂ is 2.016 g/mol.
• The molar ratio of H₂ to H₂O is 2:2.
• The molar mass of H₂O is 18.02 g/mol.

The mass of H₂O obtained from 200.0 kg (200.0 × 10³ g = 2.000 × 10⁶ g) of H₂ is:

$2.000 \times 10^{6} gH_{2}.\frac{1molH_{2}}{2.016gH_{2}} .\frac{2molH_{2}O}{2molH_{2}} .\frac{18.02gH_{2}O}{1molH_{2}O} =1.788 \times 10^{7}gH_{2}O$

Answer 2

( unknown \ known ) × value

( 2\2 ) × 200kg = 200 kg