The question as posed has no meaning - nothing spontaneously expands. Hydrogen is, at room temperature, above its Joule-Thompson inversion point. It's hard to tell if that's what you were trying to ask or not.
When hydrogen gas reacts with fluorine gas, the product formed is hydrogen fluoride (HF) gas.
Hydrogen and helium - but especially hydrogen.
No, Hydrogen is a gas. The verb "fly" can not be applied to a gas.
Hydrogen is not a noble gas.
Hydrogen is the lightest gas.
No, hydrogen gas is a pure substance.
Hydrogen is a gas at 20 degrees, Fahrenheit and Celsius, but it you are talking Kelvin, then it is a liquid.
Energy is absorbed in expanding and lifting the gas.
oxygen gas is heavier than hydrogen gas
Hydrogen gas is H2. Oxygen gas is O2.
To find the number of moles of hydrogen gas, we first need to convert the mass of hydrogen gas from grams to moles using the molar mass of hydrogen gas (2 g/mol). 5.04 grams of hydrogen gas is equal to 5.04 g / 2 g/mol = 2.52 moles of hydrogen gas.
Hydrogen gas is colourless, odorless and tasteless.