Answer:
use coefficients and subscripts to determine how many atoms are in a compound. If there is no subscript or coefficient, assume it is 1. If there is a coefficient, multiply it with the subscripts. For counting cations and anions, determine first which is the anion and cation (anion = nonmetal, cation = metal), then count the number of that ion.
Example:
NaCl
one atom of Na, one atom of Cl. Since Na is a metal, it is a cation. Cl is a nonmetal, so it is an anion.
2CaCl2
2 atoms of Ca, 4 atoms of Cl. There are 2 cations, since Na is a metal, and 4 anions since Cl is a nonmetal
Answer : The correct option is, 13.7 mole
Solution : Given,
Moles of 
= 27.4 moles
The given balanced chemical reaction is,
From the balanced chemical reaction, we conclude that
As, 2 moles of react with 1 moles of 
So, 27.4 moles of react with 
moles of
Therefore, the number of moles of oxygen required are, 13.7 moles
it is water energy :) this is easy
Answer:
must have the same number of protons
Answer:
7.335 moles of Cl₂ are required to react with 4.89 miles of Al.
Explanation:
Given data:
Moles of Al = 4.89 mol
Number of moles of Cl₂ required = ?
Solution:
Chemical equation:
2Al + 3Cl₂ → 2AlCl₃
Now we will compare the moles of Al and chlorine from balance chemical equation.
Al : Cl₂
2 : 3
4.89 : 3/2×4.89 =7.335 mol
Thus, 7.335 moles of Cl₂ are required to react with 4.89 miles of Al.
