Answer:
You need to make sure the number of atoms of each element on the reactant side is equal to the number of atoms of each element on the product side. In order make both sides equal, you will need to multiply the number of atoms in each element until both sides are equal. :)
The answer is 2 more oxygen is needed
The balanced chemical equation for the combustion of butane is:

Δ
= Σ
Δ
-Σ
Δ
=
=[-3148kJ/mol+(-2418.2kJ/mol)]-[(-251.2kJ/mol)+0]
= -5315 kJ/mol
Calculating the enthalpy of combustion per mole of butane:

Therefore the heat of combustion per one mole butane is -2657.5 kJ/mol
Correct answer: -2657.5 kJ/mol
C) Stars get born, get older, then eventually die.
Answer:
C. Energy is absorbed and released during chemical reactions,
Explanation:
All chemical reactions involve energy. Energy is used to break bonds in reactants, and energy is released when new bonds form in products. Endothermic reactions absorb energy, and exothermic reactions release energy.