15. 1 were lost
16. 3 were gained
17. 2 were lost
18. 1 was gained
You can figure that out by looking at the number nest to the molecule with a plus or minus sign next to it
+ = gained
- = lost
Answer:
A.
A chemical reaction was producing a new substance.
Explanation:
Equation of the reaction
NaOH + HCl --> NaCl + H2O
Heat of neutralization is the amount of heat evolved when one mole of acid reacts with one mole of an alkaline to form one mole of water.
When a neutralisation reaction is carried out, there is an exothermic change; energy released into the surroundings therefore since heat is given out which is what is felt.
Number of molecules = moles x 6.02 x 10^23 = 2 x 6.02 x 10^23
= 1.204 x 10^24 molecule.
Hope this helps!
The direction oxygen goes is out of the cell. It secretes it.