Answer: The missing coefficient is 2.
Explanation:
According to the law of conservation of mass, mass can neither be created nor be destroyed. Thus the mass of products has to be equal to the mass of reactants. The number of atoms of each element has to be same on reactant and product side. Thus chemical equations are balanced.

As in the products, there are 2 atoms of sodium, thus there will be 2 atoms of of sodium in the reactant as well. This will balance the number of hydrogen and oxygen atoms as well.
Thus the missing coefficient is 2.
Answer:
The answer is option B, that is, it has two oxygen atoms.
Answer:
The U.S. Federal Communications Commission (FCC)
Explanation:
Answer: Ionic bond is composed of Ca2+ cations and Cl– anions; those ions are stable since they have filled valence shells. Its ionic formula is written as CaCl2, the neutral combination of these ions.
Explanation:
Answer:
20.0/1 x 1mole/58.44=0.34
(Atomic mass of salt)
Been a minute since I've done this, but this is how I remember doing it, soo..hope this helps!