Dry NO is added to 80g of Br2 and cooled to 0°C. During the introduction of the gas, the Br2 is gradually cooled to —10°C by placing the flask in a freezing mixture. The completely saturated liquid weighs about 28 g more than the initial. The reaction mixture is slowly heated; the NOBr distills at 24°C. It is collected in a cooled ampoule.
