Determine the concentrations of k2so4, k , and so42– in a solution prepared by dissolving 1.80 × 10–4 g k2so4 in 1.50 l of water. express all three concentrations in molarity. additionally, express the concentrations of the ionic species in parts per million (ppm). note: determine the formal concentration of so42–. ignore any reactions with water.

Consider the nuclear equation below. 239 > x + 4 he 94 2 what is x? 1.235 cm 96 2.243 u 92 3.235 u 92 4.243 cm 96

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.

Stage in which a star’s outer layers have started to cool and grow outward?