Question

A solution contains 2 moles of hydrochloric acid.the volume of the solution is 250 cm3

what is its concentration in mol/dm³ ​

Answer 1

1dm = 10cm

1dm3 = 10cm x 10cm x 10cm = 1000cm3

1L = 1000cm3

so 1litre = 1dm3

4 moles in 2 dm3

= 2 moles in 1dm3 = 2moles in 1L = 2M

1L = 1000cm

0.3 moles in 200cm3 =

200cm3 = 0.2L

so 0.3 moles in 0.2 L = 1.5 moles in 1 L = 1.5M

(I have tried to simplify and show why 1dm3 = 1L)

I hope this helps you understand!