A reaction in which products can be converted back to reactants is described as: A - NSC Physical Sciences - Question 1 - 2016 - Paper 2

This process is known as Cracking, where large hydrocarbons are broken down into smaller, more useful ones.

To increase the rate of production of H2(g), you should increase the concentration of the H2SO4(aq). Therefore, the correct choice is D.

The relationship between the forward and reverse activation energies can be expressed as:

$E_a^{forward} = E_a^{reverse} - ext{ΔH}$ Substituting the values, we have: $E_a^{forward} = 180 ext{ kJ} - (-80 ext{ kJ}) = 260 ext{ kJ}$ Thus, the answer is not directly provided here, so a selection would need to be made based on the closest alternative.

Given the concentration and Ka value, this acid is best characterized as a dilute solution of a weak acid, which indicates it does not dissociate completely in solution.

To find the final volume (V_f) needed to achieve a desired concentration, use the dilution formula:

$C_1V_1 = C_2V_2$ where $C_1 = 10 ext{ mol·dm}^{-3}$, $V_1 = 20 ext{ cm}^3$, and $C_2 = 2 ext{ mol·dm}^{-3}$.

Solving for $V_2$, we find:

$10 imes 20 = 2 imes V_f$ which simplifies to $V_f = 100 ext{ cm}^3$. Therefore, the answer is A.

Adding concentrated hydrochloric acid will shift the equilibrium to the left due to the increase in Cl⁻ concentration. Therefore, the solution will likely change color, resulting in the solution turning blue.

The correct statement here is that the water becomes acidic, as the ion product of water, Kw, increases with temperature, leading to an increase in the concentration of H3O+.