Answer:
A pure solid is heated and turns into a pure liquid.
Explanation:
No colour change recorded, only change of state, hence this is a physical change - physical changes I.e. change of state and temperature are not chemical reactions.
Answer:
A
Explanation:
Because the amount of electrons in the outer shell can be a maximum of 8
Hope this helps
Answer:
11) the difference in heat energies between products and reactants
12) enthalpy change
Explanation:
The heat of reaction is defined as that energy released or absorbed as chemical substances participate in a chemical reaction. It is a term used to denote the change in energy as reactants change into products.
Another name of heat of reaction is enthalpy of reaction. It is a state function since it depends on the initial and final states of the system.
