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Calculation method

The following relations exist among mass and volume of solution, etc.

    M_a = V_aD_cW_c/100,   M_b = V_b+V_aD_c(100-W_c)/100,   W = 100M_a/M,

    M = M_a+M_b = V_aD_c+V_b = VD,   C = 1000M_a/FV,   Q = V/V_b,   1L = 1000mL

where V_a(mL), W_c(%) and D_c(g/mL) are volume, mass percentage and density of conc. NH₃ water before dilution, M_a(g) mass of dissolved NH₃ gas, V_b(mL) volume of diluent water before dilution, M_b(g) mass of total water, M(g), V(mL), W(%), C(mol/L), and D(g/mL) mass, volume, mass percentage, molarity, and density of solution after dilution, Q volume of solution after dilution/volume of diluent water before dilution, F(g/mol) formula weight of NH₃.

An unknown value can be calculated with the use of relations shown above and known values.

You may use the upper table to convert concentration to density, volume of solution/volume of diluent water to concentration.

Preparetion method

Wash and dry apparatus beforehand.
1  Measure disstilled water with a measuring cylinder, and transfer the water to a beaker.
2  Measure conc. NH₃ water with another measuring cylinder, and add slowly into the beaker with stirring.
3  If you need, transfer the solution to reagent bottle and attach label showing the reagent's name, concentration, date, the person who prepared.

Caution

Ammonia gas evaporates from conc. ammonia water to the space (air) avobe the solution in a bottle.  So, the bottle of conc. ammonia water is filled with NH₃ gas.  When you open the cover spray may appear.  Be careful for neither gas nor mist to get in contact with the eyes.  Moreover, there is toxicity in the gas and it has a extremely pungent smell.  Deal with it in a well ventilated place so that gas may not be inhaled.

If conc. ammonia water gets in contact with the eyes or is stained with the skin, immediately wash it with water.

The presumed concentration of reagent grade chemicals is near saturation (about 28%).  When the exact concentration of dilute ammonia water is required, titrate it against a solution of an acid of known concentration, a standard solution; then, you can determine its exact concentration.