Please help :)

1.
Mg + 2HCl → MgCl2 + H2
Is the equation above balanced? How do you know?

2.
Give an example of a substance changing temperature and what happens to the motion of molecules as the temperature changes?

What does the process of natural selection involve

16. why must the number of electrons lost equal the number of electrons gained in every redox reaction? use 3 – 4 sentences in your own words to address this question. 18. what type of radiation is emitted when chromium-51 decays into manganese-51? show the nuclear equation that leads you to this answer. 19. a radioactive nucleus alpha decays to yield a sodium-24 nucleus in 14.8 hours. what was the identity of the original nucleus? show the nuclear equation that leads you to this answer.

Why can water dissolve many ionic compounds