37502 The volume of \(0.1 \,M\) \({H_2}S{O_4}\) that is needed to completely neutralise \(40\, ml\) of \(0.2 \,M\) \(NaOH\) is.....\(ml\)
(c) \({N_1}{V_1}\; = \;{N_2}{V_2}\) $⇒$ \(0.2 \times {V_1} = 0.2\, \times 40 \Rightarrow {V_1} = 40\,ml\)
37503 What volume of water is to be added to \(50 \,ml\) of \(4 \,N\) \(NaOH\) solution to obtain a \(1\, N\) solution.....\(ml\)
\(4\, N \,NaOH =50\, ml\)\(1\, N \,NaOH = ?\)\(\therefore \quad N_1 V_1=N_2 V_2 \quad, N_1=4, V_1=50,N_2=1, v_2= ?\)\(\therefore 4 \times 50=1 \times v_2\)\(v_2=200\, ml\)\(\therefore\) volume of water \(=200-50=150 \,ml\)
37504 In alkaline condition \(KMnO_4\) reacts as follows,\(2KMNO_4\) + \(2KOH\) \( \to \) \(2K_2MnO_4\) + \(H_2O\) + \(O\)The eq. wt. of \(KMnO_4\) is
(c) \(M{n^{ + 7}} \to M{n^{ + 6}} = \frac{{158}}{1} = 158\)
37505 When a standard solution of \(NaOH\) is left in the air for a few hours,
\(NaOH\) is deliquescent in nature. It absorbs water from the atmosphere and therefore, the strength of solution decreases.