556 APPENDIX 
This amount of water should be added, after which the solution will 
be exactly normal. It should be checked, however, against the N HCl. 
From this the N/20 NaOH may be prepared by diluting 50 c.c. of the 
N NaOH to a liter. 
N Potassium Hydroxide. Dissolve 56 gms. of KOH in 1000 c.c. of 
distilled water and standardize against N HClas was done with N NaOH. 
N Sodium Carbonate. Ignite the bicarbonate NaHCOs to redness 
and dissolve 53 gms. in a liter of water. Standardize against normal 
acid and dilute accordingly with distilled water. 
N Sulphuric Acid. Follow the procedure which has been given else- 
where for N HCl. This may be standardized against N NaOH or gray- 
imetrically by precipitating with BaOH. 
N Hydrochloric Acid. This should contain 36.46 gms. of HCl in 
a liter of water. The pure concentrated HCl may be diluted to a 
specific gravity of 1.020. According to the table on page 559, it will be 
seen that this solution is too strong, having about 4.13 gms. of HCl in a 
liter. To be made exactly normal, it should be titrated against pure 
NaeCO3. This is obtained by heating the NaHCOs3 being careful not 
to allow it to fuse. This is then put into a weighing bottle from which 
it 1s weighed into Erlenmeyer flasks for titrating. Dissolve in boiled 
distilled water and titrate with the HCl solution using methyl orange as 
the indicator. Calculations are made as follows, assuming for example 
that 1.9864 gms. of Na2COs neutralized 37.28 ¢.c. of the HCl solution. 
If our solution had been exactly normal 1 liter would have neu- 
tralized 
NasOs _ 106.00 =53 gms. of NasCOs 
2 2 
53 : 1000 =.1.9864°: x 
2=37 48. 
37.28 ¢.c. of the HCl solution were required and it is evident that 
this solution is too strong and that for each 37.28 c.c. of the solution, 
37.48 — 37.28 = .20 ¢.c. of water must be added. The amount of water 
to be added to each liter of the HCl solution to make it exactly normal 
is computed as follows: 
37.28: .20=1000: x 
x= amount of distilled water to be added. 
N Nitric Acid. See preparation of N HCl. 
N Oxalic Acid. Dissolve 47 gms. of pure dry oxalic acid in 1000 c.c. 
of distilled water. Standardize against N NagCOsz. 
