Hydrogen Peroxide 10 %: the 3 % Solution Evaporated in Air at 75 °C, Checked with Permanganate (Thorpe 1912)

Water evaporates faster than hydrogen peroxide, so warming a weak solution in open air makes it stronger. Thorpe gives 75 °C for this first stage; we stop at 10 %, checking the strength with permanganate. Result: hydrogen peroxide of about 10 %. Source: Thorpe, Dictionary of Applied Chemistry, vol. 3 (1912), Hydrogen peroxide. Thorpe takes it on to 20 %; stopping at 10 % is ours. Danger: 10 % peroxide burns skin and eyes. Picture drawn by Youblob.

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안내

Evaporate the 3 % solution in air at 75 °C

Warm 3 % hydrogen peroxide in an open dish at 75 °C so the water evaporates. Thorpe goes on to 20 %; ours: stop near 10 %, about a third of the starting volume. Wear goggles and gloves.

이 단계의 재료:

과산화수소 (3 %)1 as required

필요한 도구:

증발 접시

수조

실험용 온도계

화학물질 비산 보안경

고무장갑

Check the strength with permanganate

Titrate 2 c.c. in a 35 c.c. graduated tube with 5-6 drops of hydrochloric acid and a solution of 7.9 g potassium permanganate per litre until it turns red or brownish; 5 c.c. means 1 %. Ours for 10 %: dilute 1 c.c. to 2 c.c. first, so 25 c.c. means 10 %.

필요한 도구: