Exercise 2 solution

(a) 4% of 250 g = 250 x 0.04 = 10 g of sodium hypochlorite (Python: 10.0). Sodium hydroxide at 0.5% would be 1.25 g (Python: 1.25), though the question does not ask for it.

(b) The GHS hazard pictograms article lists GHS05 as Corrosive: substances that corrode metals or cause severe skin or eye damage. The signal word "Danger" is one of the two signal words the page mentions ("Danger" or "Warning"). The page does not say which pictograms take which word.

(c) Do not add vinegar. The Bleach article says "Mixing an acid cleaner with a hypochlorite bleach can cause toxic chlorine gas to be released" and that bleach "should never be mixed with vinegar or other acids". Vinegar is an acid (Chapter 8). The product contains sodium hypochlorite, so the same warning applies (my application of the article to this invented product (check)). Use it as the label says, with ventilation, and never mix it with other cleaners.

Note: the product and its figures are invented.