When an object with an electric charge of -9.0uC is 4.0 cm from an object with an electric charge of 5uC , the force between them has a strength of 252.8 N . Calculate the strength of the force between the two objects if they are 12cm apart.

Round your answer to significant digits.

2. how is heavy water different from normal water

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.

Which terms are used to identify pure substances