Given the mass of aluminum sulfide
= 21.0 g
Molar mass of
= 
Calculating the moles of
:

Each mole
has 3 mol S.
Each mole S constitutes 
Calculating atoms of S in 0.14 mol
:

= 
Answer:
Label 2
Explanation:
Earth is about 2/3 of the way up the Orion Arm of the Milky Way Galaxy
Answer:
The order of elements by volume-fraction (which is approximately molecular mole-fraction) in the atmosphere is nitrogen (78.1%), oxygen (20.9%), argon (0.96%), followed by (in uncertain order) carbon and hydrogen because water vapor and carbon dioxide, which represent most of these two elements in the air, are variable.
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