Question

\(${20 mL}$\) of \(${ 0.5\, N\, HCl}$\) and \(${35\, mL}$\) of \(${0.1 \,N\, NaOH}$\) are mixed. The resulting solution will

• A. be neutral
• B. be basic
• C. turn phenolphthalein solution pink
• D. turn methyl orange red.

Answer 1

The Correct Option is D

\(${20 \, mL}$\) of \(${0.5\, N\, HCl = 20 \times 0.5\, milli e}$\) \(${= 10\, milli\, e \,of \,HCl}$\) \(${35\, mL }$\) of \(${ 0.1\, N \, NaOH = 35 \times 0.1\, milli \, e}$\) \(${= 3.5\, milli \, e \, of \, NaOH.}$\) Thus, \(${3.5\, milli \, e \, of \, NaOH }$\) will neutralize ${3.5 milli \, e\, of \, HCl (10 - 3.5) = 6.5 \, milli \, e \, of \, HCl}$ will be left. Therefore, solution will be acidic and it will turn methyl orange red.