Question

What is the molarity of 2M nacl solution, 400ml of which is diluted to 700 ml

Answer 1

Let the initial volume of NaCl solution be
$v_{1}$
= 400 ml
final volume =
$v_{2}$
= 700 ml

Ititial Molarity =
$m_{1}$
= 2M

we have to find final Molarity say
$m_{2}$

Now we know the relationship between Molarity and volume...

$m _{1} \times v_{1} = m_{2} \times v_{2}$

Now Plugin the values we get...
2×400 = m2 × 700
=> 8/7 = m2
hence m2 = 1.14M approx