PLEASE HELP ME IM STUCK The lawyer is in a very big hurry and needs her tea party to end as quickly as possible. She debates whether to set out sugar cubes or granulated sugar. Which will she most likely select for the guests to use for their tea? Give a scientific reason for her choice.

1. calculate the approximate enthalpy of the reaction in joules. estimate that 1.0 ml of vinegar has the same thermal mass as 1.0 ml of water. iqnore the thermal mass of th sodium bicarbonate. note: it takes about 4.2 joules () to change 1.0 gram (1.0ml) of water 1.0 c

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 of the following is an example of physical change not a chemical change? a) a log gives off heat and light as it burns. b) a tree stores energy from the sun in its fruit. c) a penny lost in the grass slowly changes color. d) a water pipe freezes and cracks on a cold night.