Question

the no of ions present in 1ml of 0.1m cacl2 solution is

Answer 1

 0.1M solution means that you have 0.1 mol of CaCl2 in 1000mL solution  

But CaCl2 ↔ C+ 2+ + 2Cl- = 3 ions / molecule  

Therefore the 0.1M CaCl2 solution = 0.3M in respect of ions.  

You have 0.3 mol ions in 1000 mL solution  

You have 0.3/1000 = 0.0.0003 mol ions in 1 mL solution  

Number of ions:  

1 mol of ions = 6.022*10^23 ions  

0.0003 mol ions = (0.0003)*(6.022*10^23) = 1.81*10^20 ions.