hydrogen and carbon, hope that helped
Heat is needed to change solid to liquid even to gas!
Balanced chemical reaction: A + 5C ⇄ AC₅.
<span>[A] = 0.100 M; equilibrium concentration.
</span><span>[C] = 0.0380 M.
</span>[AC₅] = 0.100 M.
Kf = [AC₅] / ([A] · [C]⁵).
Kf = 0.100 M ÷ (0.100 M · (0.0380 M)⁵.
Kf = 12620658.54 = 1,26·10⁷.
<span>The formation constant can be calculated when </span>chemical equilibrium is reached, when the forward reaction rate is equal to the reverse reaction rate.
Answer: (C) conservation of matter
Solution: Law of conservation of matter or mass states that' total mass of the reactants should always be equal to the total mass of the product that is the total mass is remained conserved in a chemical reaction.
A balanced chemical equation always follow this law.
For example:

Mass of hydrogen = 1 g/mol
Mass of Oxygen = 16 g/mol
Total mass on the reactants = 2(2×1)+(2×16)= 36g/mol
Total mass on the product side = 2[(2×1) +16] = 36 g/mol
As,
Mass on reactant side = Mass on the product side
Therefore, a balanced chemical reaction follows Law of Conservation of mass.
As what we can see on the graph of the Boyle's Law, we can imply that volume and pressure are inversely proportional. The gas law furthermore explains that at this condition, the temperature must be held constant. The law can be furthermore be explained using the equation:
PV = k