Answer : The correct option is, (D)
Explanation :
Option A reaction : 
It is a combustion reaction. A reaction in which a hydrocarbon react with the oxygen to give product as carbon dioxide and water.
Option B reaction : 
It is a combination reaction. A reaction in which the two or more reactants react to give a product.
Option C reaction : 
It is a decomposition reaction. A reaction in which a reactant decomposes to form two or more products.
Option D reaction : 
It is a single displacement reaction. It is a reaction in which the more reactive element displace the less reactive element. In this reaction, most reactive element chlorine displaces the less reactive element bromine.
Hence, the correct option is, (D)
This is true, think of silver, gold, etc— those are heated to make them liquid
There are approximately 160 grams in 1 mol of Fe2O3 molecules. Therefore, there would be 79/160= 0.49375 mols of Fe2O3 molecules in 79 grams. There are 5 atoms in total for each molecule of Fe2O3, therefore 79/160 * 5 = 79/32 = 2.46875 mols of atoms.
The answer is: mass is 40.17 kilograms.
d = 0.758 g/mL; density of fuel.
V = 14.0 gal; volume.
A gallon is a unit of volume in both the US customary and imperial systems of measurement. The US gallon is defined as 231 cubic inches (3.785 liters).
1 gal = 3785.41 mL.
V = 14 gal · 3785.41 mL:
V = 52995.74 mL.
m = 52995.74 mL · 0.758 g/mL.
m = 40170.77 g; mass of fuel.
m = 40170.77 g ÷ 1000 g/kg.
m = 40.17 kg.