Following solutions were prepared by mixing different volumes of NaOH and HCl of different concentrations:(a) 60 ml, (M)/(10) HCl + 40 ml (M)/(10) NaOH (b) 55ml, (M)/(10) HCl +45 ml (M)/(10) NaOH (c) 75ml , M/5 HCl + 25ml M/5 NaOH (d) 100 ml, M/5 HCl + 100 ml (M)/(10) NaOH pH of which one of them will be equal to 1?

Following solutions were prepared by mixing different volumes of NaOH

1.	Following solutions were prepared by mixing different volumes of NaOH and HCl of different concentrations:(a) 60 ml, (M)/(10) HCl + 40 ml (M)/(10) NaOH (b) 55ml, (M)/(10) HCl +45 ml (M)/(10) NaOH (c) 75ml , M/5 HCl + 25ml M/5 NaOH (d) 100 ml, M/5 HCl + 100 ml (M)/(10) NaOH pH of which one of them will be equal to 1?
Answer» c b d a Solution :`75ml M/5 HCl + 25 ml M/5 NAOH` ` THEREFORE (75-25) = 50ml M/5 + HCl` REMAIN Total volume=100ml x m `1/5 M xx 50 ml = 100 ml xx xm` ` therefore x= 1/5 xx 50 xx 1/100 = 1/10 M HCl =[H^+]` ` therefore PH = -log (1/10) = 1.0`