| Herbert B. Berkeley recommended the use of sulphite of soda with pyrogallic acid to prevent discolouration of film. |
| Among the better known agents which have such an effect upon latex, formalin and sodium sulphite are the chief. |
| They breathe compounds such as CO2, sulphate, sulphite, certain oxidised metals. |
| By reaction with sodium sulphite it is converted into a hydroquinone sulphonate of deep purple colour. |
| During primary sulphate assimilation in chloroplasts, sulphate is reduced via sulphite to the organic sulphide which is used for cysteine biosynthesis. |
| The solution is diluted with water, and treated with a solution of sulphite of soda. |
