For formation of a neutral ionic compound, the charges on cation and anion must be balanced. The cation is formed by loss of electrons by metals and anions are formed by gain of electrons by non metals.
The cations and anions being oppositely charged attract each other through strong coloumbic forces and form an ionic bond.
(1) Sodium is carrying +1 charge called as cation and chloride is an anion carrying -1 charge. Thus they combine and their oxidation states are exchanged and written in simplest whole number ratios to give neutral .
(2) Sodium is carrying +1 charge called as cation and phosphate is an anion carrying -3 charge. Thus they combine and their oxidation states are exchanged and written in simplest whole number ratios to give neutral .
(3) Sodium is carrying +1 charge called as cation and sulfate is an anion carrying -2 charge. Thus they combine and their oxidation states are exchanged and written in simplest whole number ratios to give neutral .
(4) Sodium is carrying +1 charge called as cation and carbonate is an anion carrying -2 charge. Thus they combine and their oxidation states are exchanged and written in simplest whole number ratios to give neutral .
(5) Potassium is carrying +1 charge called as cation and chloride is an anion carrying -1 charge. They form .
(6) Potassium is carrying +1 charge called as cation and phosphate is an anion carrying -3 charge. They form .
(7) Potassium is carrying +1 charge called as cation and sulfate is an anion carrying -2 charge. They form .
(8) Potassium is carrying +1 charge called as cation and carbonate is an anion carrying -2 charge. They form .
(9) Calcium is carrying +2 charge called as cation and chloride is an anion carrying -1 charge. They form .
(10) Calcium is carrying +2 charge called as cation and phosphate is an anion carrying -3 charge. They form .
(11) Calcium is carrying +2 charge called as cation and sulfate is an anion carrying -2 charge. They form .
(12) Calcium is carrying +2 charge called as cation and carbonate is an anion carrying -2 charge. They form .
(13) Ammonium ion is carrying +1 charge called as cation and chloride is an anion carrying -1 charge. They form .
(14) Ammonium ion is carrying +1 charge called as cation and phosphate is an anion carrying -3 charge. They form .
(15) Ammonium ion is carrying +1 charge called as cation and sulfate is an anion carrying -2 charge. They form .
(16) Ammonium ion is carrying +1 charge called as cation and carbonate is an anion carrying -2 charge. They form .
(17) Iron is carrying +3 charge called as cation and chloride is an anion carrying -1 charge. They form .
(18) Iron is carrying +3 charge called as cation and phosphate is an anion carrying -3 charge. They form .
(19) Iron is carrying +3 charge called as cation and sulfate is an anion carrying -2 charge. They form .
(20) Iron is carrying +3 charge called as cation and carbonate is an anion carrying -2 charge. They form .
To figure out questions related to reacting moles/masses, the first step is always to write a complete balanced equation.
2Fe (s) + 3Cl2 (g) → 2FeCl3 (s)
Since Cl2 is the excess reactant, and Fe is the limiting reactant, we can simply find the number of moles of the product by comparing the mole ratio of the limiting reactant to the mole ratio of the product from the equation.
From the equation, mole ratio of Fe:FeCl3 = 2:2 = 1:1, the number of moles of product is exactly the same as the number of moles of the limiting reactant, which makes it 8 moles.
Note that if the mole ratio is not 1:1, you have to do some calculations to make sure the no. of moles is balanced at the end. Which means, if the mole ratio happened to be 1:2, the no. of moles of the product would be 8x2=16 instead.