Answer:
Explanation:
The change in enthalpy of a substance when heated is given by
ΔH = m x Csp x ΔT
so the enthalpy change is dependent on the specific heat , i.e its capactity to absorb heat, and is not influenced by factors such as being closer to the melting point, volume , potential energy or being a solid or liquid.
It is 1-3-1-3
so 1Al2O3 + 3H2So4 ---> 1Al2(So4)3 + 3H2O
The third one down: "When barium hydroxide is mixed with ammonium chloride, ice crystals form on the outside of the container."
This is because an endothermic reaction [process] takes in more energy than it releases. Therefore because a decrease in energy leads to a decrease in temperature, the ice crystals forming show that it must be a endothermic reaction [process].
Hope this helps! :)
AJ