Be sure to answer all parts. draw two resonance structures for each species − one that obeys the octet rule, and one in which the formal charge on the central atom is zero. show all formal charges and nonbonding electrons. obeys octet rule draw structure po43− zero formal charge on the central atom draw structure obeys octet rule draw structure hclo3 zero formal charge on the central atom draw structure obeys octet rule draw structure so3 zero formal charge on the central atom draw structure obeys octet rule draw structure so2 zero formal charge on the central atom draw structure

Long term exposure to waves can cause sunburns and skin cancer. a) visible b) infrared c) gamma rays d) ultraviole

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.

How is energy related to the change of state represented by the model? atoms gain energy as a solid changes to a liquid. atoms gain energy as a solid changes to a gas. atoms lose energy as a solid changes to a liquid. atoms lose energy as a solid changes to a gas.