Question

Find the no. of H+ ions present in 250 ml of lemon juice of pH = 2​

Answer 1

Answer:

pH=3 so H+=10−3M means 10−3 moles of H+ are present in 1000 mL of solution.

Number of moles of H+ ions in 250mL=100010−3= 0.25×10−3. 

Number of moles of H+ ions in 250mL=0.25×10−3×6.023×1023=1.506×1020. 

Answer 2

$\huge\bf\purple{Good\: Afternoon}$

⚽ pH = 2

We know that,

$\longmapsto~\bf\pink{pH~=~-~log~[H^+]~}$

$\longmapsto~\bf{[H^+]~=~10^{-pH}~}$

$\longmapsto~\bf{[H^+]~=~10^{-2}~M}$

• Means $\sf{10^{-2}}$ moles of $\sf{H^+}$ are present in 1000 mL of solution.

⚽ Number of moles of $\sf{H^+}$ ions in 250mL is,

╰➝ $\sf{\dfrac{10^{-2}}{1000}\times{250}\times{N_A}}$

╰➝ $\sf{2.5\times{10^{-3}}\times{6.023\times{10^{23}}}}$

╰➝ $\sf\green{15.0575\times{10^{20}}~Moles}$