Question

calculate the molarity of naoh in the soultion prepared by disaolving its 4g in enough water to torm 250 ml of the solution​

Answer 1

Answer:

molarity = no of moles of solute / volume of solution in litre

no of moles = 4/40 = 0.1

volume in litre = 250 / 1000 = 0.25

molarity = 0.1 / 0.25 = 0.4

Explanation:

Answer 2

$\huge\sf\pink{Answer}$

☞ Your Answer is 0.4 mol $\sf \ L^{-1}$

━━━━━━━━━━━━━

$\huge\sf\blue{Given}$

✭ 4g of NaOH is dissolved in enough water make 250 ml of Solution

━━━━━━━━━━━━━

$\huge\sf\gray{To \:Find}$

◈ The Molarity?

━━━━━━━━━━━━━

$\huge\sf\purple{Steps}$

We know that,

$\small\underline{\boxed{\sf Molarity = \dfrac{Number \ of \ moles \ of \ Solution}{Volume \ of \ Solution}}}$

So the number of moles of the solution let it be say 'N' is given by,

$\underline{\underline{\sf N = \dfrac{Given \ Weight}{Molecular \ Weight}}}$

◕ Give Weight = 4g

◕ Molecular Weight = 40

Substituting the given values,

➝ $\sf N = \dfrac{4}{40}$

➝ $\sf N = \dfrac{1}{10}$

➝ $\sf \red{N = 0.1 \ mol}$

Now we shall substitute the value of the number of moles in the first formula,

➳ $\small\sf Molarity = \dfrac{Number \ of \ moles \ of \ Solution}{Volume \ of \ Solution}$

➳ $\sf Molarity = \dfrac{0.1}{\dfrac{250}{1000}}$

➳ $\sf Molarity = \dfrac{0.1}{0.25}$

➳ $\sf Molarity = \dfrac{10}{25}$

➳ $\sf \orange{Molarity = 0.4 \ mol \ L^{-1}}$

━━━━━━━━━━━━━━━━━━