Uses
Sodium hypobromite is an inorganic salt compound, which can be used as an intermediate in the synthesis of medicine and chemical industry.
Preparation
Sodium hypobromite can be prepared by the following methods:dissolve part of sodium hydroxide in water, cool it to below 10°C, add bromine to react, and keep the temperature below 10°C.
Chemical Properties
Formula weight (NaBrO) 118.91. Yellow crystals, readily
soluble in H2O. May be stored at —20°C in a closed weighing
vessel for a few days with only slight loss of NaBrO; decomposition, with formation of NaBr and NaBrO3, begins immediately at 0°C and is complete within two days. Analysis after drying for one or two hours on clay at 0°C; about
92% NaBrO·5H2O, 2% NaBr·2H2O, 1% NaBrO3, 5% moisture.
Synthesis
A 40% sodium hydroxide solution (438 g., 306 ml.) is stirred
and cooled to —3°C in a wide-neck, round-bottom flask closed
with a three-hole rubber stopper (for a stirrer, dropping funnel
and thermometer). Bromine (314 g., 100 ml., 90% of the quantitj
theoretically needed for 175 g. of NaOH) is slowly added (1-2
drops per second) with constant stirring. The temperature of the
reaction mixture is held between —8 and —3°C. Insufficient cooling
results in the formation of NaBrO3; cooling below —8°C should be
avoided to prevent slow solidification of the flask contents.
Br2 + 2 NaOH + 4 H2O = NaBrO ? 5 H2O + NaBr
