Hydrochloric acid (sp. gr. 1.20) contains 39.80 per cent HCl by weight, and corresponds to a 13.1 N and 13.1 molal solution.

Nitric acid (sp. gr. 1.20) contains 32.25 per cent HNO_{3} by weight, and corresponds to a 6.1 N and 6.1 molal solution:

Nitric acid (sp. gr. 1.42) contains 69.96 per cent HNO_{3} by weight, and corresponds to a 15.8 N and 15.8 molal solution.

Sulphuric acid (sp. gr. 1.8354) contains 93.19 per
cent H_{2}*so*_{4} by weight, and corresponds to
a 34.8 N or 17.4 molal solution.

Sulphuric acid (sp. gr. 1.18) contains 24.74 per cent
H_{2}*so*_{4} by weight, and corresponds to a 5.9
N or 2.95 molal solution.

The term !normal! (N), as used above, has the same significance as in volumetric analyses. The molal solution is assumed to contain one molecular weight in grams in a liter of solution.

*Densities* *and* *volumes* *of* *water*
*at* *temperatures* *from* 15-30 deg.C.

Temperature Density. Volume.

Centigrade.

4 deg. 1.000000 1.000000 15 deg. 0.999126 1.000874 16 deg. 0.998970 1.001031 17 deg. 0.998801 1.001200 18 deg. 0.998622 1.001380 19 deg. 0.998432 1.001571 20 deg. 0.998230 1.001773 21 deg. 0.998019 1.001985 22 deg. 0.997797 1.002208 23 deg. 0.997565 1.002441 24 deg. 0.997323 1.002685 25 deg. 0.997071 1.002938 26 deg. 0.996810 1.003201 27 deg. 0.996539 1.003473 28 deg. 0.996259 1.003755 29 deg. 0.995971 1.004046 30 deg. 0.995673 1.004346

Authority: Landolt, Boernstein, and Meyerhoffer’s !Tabellen!, third edition.

CORRECTIONS FOR CHANGE OF TEMPERATURE OF STANDARD SOLUTIONS

The values below are average values computed from data relating to a considerable number of solutions. They are sufficiently accurate for use in chemical analyses, except in the comparatively few cases where the highest attainable accuracy is demanded in chemical investigations. The expansion coefficients should then be carefully determined for the solutions employed. For a compilation of the existing data, consult Landolt, Boernstein, and Meyerhoffer’s !Tabellen!, third edition.

Corrections
for 1 cc.

Concentration.
of solution between

15
deg. and 35 deg.C.

Normal .00029 0.5 Normal .00025 0.1 Normal or more dilute solutions .00020

The volume of solution used should be multiplied by the values given, and that product multiplied by the number of degrees which the temperature of the solution varies from the standard temperature selected for the laboratory. The total correction thus found is subtracted from the observed burette reading if the temperature is higher than the standard, or added, if it is lower. Corrections are not usually necessary for variations of temperature of 2 deg.C. or less.