The answer for four is frequency.
<span>The choices are as follows:
h2o + 2o2 = h2o2
fe2o3 + 3h2 = 2fe + 3h2o
al + 3br2 = albr3
caco3 = </span><span>cao + co2
The correct answers would be the second and the last option. The equations that are correctly balanced are:
</span> fe2o3 + 3h2 = 2fe + 3h2o
caco3 = cao + co2
To balance, it should be that the number of atoms of each element in the reactant and the product side is equal.
We know that there are 100 cm in 1 m, so we need to add that into the conversion:
Or, in scientific notation:
The atomic number is the amount of protons in a nucleus, while the mass number is the protons plus neutrons.
Atomic number: 8
Atomic mass : 8+8 = 16
Answer: Atomic mass is 16, while atomic number is 8