What is the concentration of a solution containing 2g of NaOH in 100cm³ of solution?
[Na = 23, O = 16, H = 1]

obedvictor

9 years ago

Here is an explanation:

mass given =2g

Vol given =100cm³

M=m/mm

mole=mass/molar mass.

Molar mass=40gmol-¹

Na+O+H=23+16+1=40gmol-¹

Molar conc=mass×1000cm³/molar mass×vol

Molar conc of the solution=2×1000/40×100

Molar conc=0.5mol/dm³





Do you understand?

Prudentjoe19

11 years ago

Cm = no of moles/volume.

But n=m/M.M =2/40=0.05mole

now Cm = n/v

but v=100/1000=0.1dm3

Cm=0.05/0.1 = 0.5mol.dm3

AKPEBOY16

9 years ago

Here is an explanation:

Concentration =Amount /volume



but amount=mass/molar mass

molar mass of NaOH =40gmol-1

reacting mass =2g

vol.=100 /1000, which is 0.1dm3

amount =2/40,= 0.05moles

concentration =0.05/0.1 = 0.50mol/dm3

favourite3491

5 years ago

Thank you

Anela

1 year ago

Quick formula;
m/mm. =cv/1000
substitute and solve

@materamabilis01

3 months ago

thanks

doctorfunmilade82

3 months ago

its very simple and dirct. use this formula. mass/molar mass = concebtration in moldm3 x volumee in cm3/1000. thus concentration in moldm3 = 20 x 1000/ 40 x 100 = 0.5moldm3

adenikeilorin

12 years ago

u hav 2 explain hw u arrrive at ur ans