The half-reaction at the cathode in an electrochemical cell is given below. What other half-reaction would most likely occur at the anode to produce a
spontaneous reaction?
Zn2+(aq) + 2e → Zn(s)
Click for a reduction potential chart
O A. H2(9) → 2H+(aq) + 2e
B. Al(s) → A13+ (aq) + 3e
O C. Zn(s) → Zn2+ (aq) + 2e
O D. K*(aq) + e
->
K(s)

Sylvanite is a mineral that contains 28.0% gold by mass. how much sylvanite would you need to dig up to obtain 77.0 g of gold? explain how you got your answer and the steps you took. you

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.

8.98 dm3 of hydrogen gas is collected at 38.8 °c. find the volume the gas will occupy at -39.9 °c if the pressure remains constant.