Procedures that are likely a chemical change are:
- Bubbles were produced when iron was placed in acid.
- Two liquids were combined, and a solid appeared
- A white substance turned blue when water was added.
The answer is 3. The releasing of energy means exothermic reaction. So the ΔH should be negative. And the greatest quantity of energy released means that the greatest number. So according to the table I, the answer is 3.
I'm not sure but i would say C.storing the heat energy.
Mole ratio for the reaction is 1:1
no of moles in NaOH that reacted= 1*21.17/1000=0.02117mols
molarity of HCl=0.02117*10/1000
=2.117M
D. Chemical and Physical Properties