Hello!! Your atomic mass will be found at the bottom of each element. The atomic mass of Nitrogen is 14.007. Have a great day!!
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
Answer: m= 1.02x10² g AlCl3 or 1091.3 g AlCl3
Explanation: solution attached.
Convert mass of Mg to moles
Do the mole ratio between Mg and AlCl3 based from the balanced equation.
Convert moles of AlCl3 to mass using its molar mass.
The answer is D because they would have to make quarries just below the surface to mine
Mineral ores much quicker (Quarries- a large hole/pit under ground used to get stone and minerals)
1=c 2=a 3=b
i hope these answer your questions