2 g (an excess) of iron is added to 50 cm3 of 0.5 M sulfuric acid. When the reaction is over, the reaction mixture is filtered. The mass of the unreacted iron is found to be 0.6 g. (Ar : Fe 5 56.) a What mass of iron took part in the reaction? b How many moles of iron atoms took part? c How many moles of sulfuric acid reacted? d Write the equation for the reaction, and deduce the charge on the iron ion that formed. e What volume of hydrogen (calculated at rtp) bubbled off during the reaction?

The scheme below is from a series of reactions that are part of a synthesis of vitamin a. answer the following questions with reference to this scheme. (i) what is "reagent a"? (ii) draw a step-by-step mechanism which explains the formation of compound c from compound b (iii) which reagents would you use to form compound e from compounds c and d (reagents b and c)? for each reagent suggested above in (ii) explain the role of the reagent in the reaction to (iv) form compound e. you may wish to do this by drawing a mechanism. 1. addition of reagent a но reagent a 2. н,о" thо oh нон-с compound a. compound b. compound c .ch-оh 1. reagent b "сно 2. reagent c сh oh compound e. compound d.