Well a mixture is less permanent and also it can be easily taken aprt where a compound does the opposite of those things.
Hope I helped :)
A because if you multiple it, you will be moving the decimal one time
Answer:

Explanation:
Half time is period required to desintegrating the half of the initial number of atoms. Then, the total time is:


Explanation:
Over 99.9% percent of an atom's mass resides in the nucleus. The protons and neutrons in the center of the atom are about 2000 times heavier than the electrons orbiting around it.
Because the electrons are so light by comparison,they represent only a tiny fraction of a percent of the atom's total weight.
Hope this answer helps you!
Answer: 4 HCl (g) + O₂ (g) → 2 Cl₂ (g) + 2 H₂O (l)
Explanation:
4 moles of hydrogen chloride (note that it is in the gaseous phase, otherwise it would be hydrochloric acid) react with 1 mole of oxygen gas to form 2 moles of chlorine gas and 2 moles of liquid water.
To conform with the law of conservation of mass, the equation must be balanced, this means that there must be the same number of each type of atom on both sides of the arrow.