Calculate the sodium ion concentration when 70.0 ml of 3.0 m sodium carbonate is added to 30.0 ml of 1.0 m sodium bicarbonate.

Answer : The concentration of sodium ion is, 4.5 mole/L

Solution : Given,

Concentration of sodium carbonate = 3 mole/L

Concentration of sodium bicarbonate = 1 mole/L

Volume of sodium carbonate = 70 ml = 0.07 L      (1 L = 1000 ml)

Volume of sodium carbonate = 30 ml = 0.03 L

First we have to calculate the moles of sodium carbonate and sodium bicarbonate.

As we know that there are 2 sodium ion present in sodium carbonate and 1 sodium ion in sodium bicarbonate. Thus, the total moles of sodium ion will be,

Now we have to calculate the concentration of sodium ion.

Total volume = 0.07 + 0.03 = 1 L

Therefore, the concentration of sodium ion is, 4.5 mole/L

since electrons are negative the answer is neagtaive