Question

the total number of ions present in 1 ml of 0.1 m. Barium nitrate solution

(1) 6.02 x 108

(2) 6.025 x 1010

(3) 3.0 x 6.03 x1019

(4) 3.0 x 6.02 x 10 10

Answer 1

Hello

Molarity = moles/litre

0.1 = X . 1000/1  ( converted  into ml)

X = 10-4 moles or 0.0001 moles

and we know that Ba(NO3)2 dissociates into Ba2+ + 2NO3-

the total no of ions = 3 in one mole 

so in 10-4 moles = 

3 . 10-4 . 6.023.1023

Answer 2

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