The Lost Cross and Mandatory Lab 6.1

Mandatory Lab 6.1 refers to ‘Investigation of rates of reaction experimentally and evaluation of the results’. Here, in the UK, I have been introduced to a new way of carrying out the ‘lost cross’ experiment with respect to changing the temperature. The experiment is a classic. A solution of sodium thiosulfate is added to hydrochloric acid. Over time, a precipitate of sulfur is produced: 2HCl(aq) + Na2S2O3(aq)  --> 2NaCl(aq) + SO2(g) + S(s) + H2O(l) The initial rate of reaction can be measured by timing how long it ...