Answer: 8moles
Explanation:
The reaction below shows the formation of 2 moles of water from 2 moles of hydrogen and 1 mole of oxygen respectively.
2H2(g) + O2 (g) --> 2H2O(l)
So, if 1 mole of O2 produce 2 mole of H2O
4 moles of O2 will produce Z mole of H2O
To get the value of Z, cross multiply
1 x Z = 4 x 2
Z = 8
So, the equation will be 8H2(g) + 4O2 (g) --> 8H2O(l)
Thus, 4 moles of O2 will produce 8moles of H2O .
The isotope notation : ⁷³₅₃X
<h3>Further explanation</h3>
Given
53 protons and 20 neutron
Required
The isotope notation
Solution
Isotopes are elements that have the same atomic number with a different mass number
The following element notation,

X = symbol of element
A = mass number
= number of protons + number of neutrons
Z = atomic number
= number of protons = number of electrons, on neutral elements
So the mass number of element = 53 + 20 = 73
Atomic number = 53
The symbol :

As temperatures increase, additional heat energy is applied to the constituent parts of a solid, which causes additional molecular motion. Molecules begin to push against one another and overall volume of a substance increases. When thermal energy is added to a substance, it’s temperature increases.