C) 6.75 x 10^-7
Hope it helped ya
Because without the mass, you can't find the molar mass and other formulas in Chemistry.
Answer:
The correct answer is option b.
Explanation:

Mass of coal burned =
metric ton = 1.00\times 10^6\times 10^3 kg=10^9 kg[/tex]
1 metric ton = 
Molar mass of coal :

1 g = 0.001 kg
Moles of coal ,n :
If 2 moles of coal on combustion gives 270 moles of carbon dioxide than n moles of coal will give;
of carbon dioxide.
Molar mass of carbon dioxide gas = 44 g/mol = 0.044 kg/mol
Mass of
of carbon dioxide:

Greenhouse effect/climate change
Plant and crop life
Human and animal health
Oceans
Oxygen gas produced : 0.7 g
<h3>Further explanation</h3>
Given
10.0 grams HgO
9.3 grams Hg
Required
Oxygen gas produced
Solution
Reaction⇒Decomposition
2HgO(s)⇒2Hg(l)+O₂(g)
Conservation of mass applies to a closed system, where the masses before and after the reaction are the same
mass of reactants = mass of products
mass HgO = mass Hg + mass O₂
10 g = 9.3 g + mass O₂
mass O₂ = 0.7 g