Phương trình hóa học: 2Mg+O2->2Mgo
4 moles of hydrogen = 4 * 1.008 = 4.032 grams
1 mole of helium = 4.003 grams
Difference is 4.032 - 4.003
= 0.029 g
Answer is B. gas formation
The density of hydrogen : ρ = 0.0892 g/L
<h3>Further explanation</h3>
Given
mass of Hydrogen : 0.446 g
Volume = 5 L
Required
The density
Solution
Density is a quantity derived from the mass and volume
Density is the ratio of mass per unit volume
The unit of density can be expressed in g/cm³, kg/m³, or g/L
Density formula:

Input the value :
ρ = m : V
ρ = 0.446 g : 5 L
ρ = 0.0892 g/L