Question

How many moles are present in 25 ml of a 0.15m solution

Answer 1

Explanation:

According to given data, we have 0.15M solution.

1M solution is prepared by taking 1 mole of a substance and dissolving it in 1 litre of liquid. 1 litre solution means 1000ml solution

Now we have 0.15M solution, which means that 0.15 moles are present in one litre solution and from that one litre if we take only 25 ml of solution then;

Number of moles = 0.15 x 25/1000 = 0.00375 moles

Answer 2

The correct question is:-

How many moles are present in 25 ml of a 0.15 M solution?

Answer:-

Given:

25 ml of a 0.15 M solution

To Find:

Number of moles present in the given solution

Solution:

The molarity of a solution is the number of moles of a particular solute present in one litre of solution. It is denoted by 'M'

   Molarity = Number of moles / Volume of the solution (in litres)

⇒    Number of moles = Molarity x Volume of solution  ......(i)

Volume of the solution = 25 ml = 25/1000 l  (∵ 1 ml = 1/1000 l)

and molarity = 0.15 (Given)

Putting the given values in equation (i), we get

Number of moles = 0.15 x 25 / 1000 = 0.00375

Hence, the given solution contains 0.00375 moles