A student decides to conduct an investigation to determine the boiling points of water and ethanol. The student will heat samples of water and ethanol, and measure the temperature at which the samples boil. The student will conduct the investigation three times. Which aspect is missing from the experimental design?

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.

An animal cell loses the ability to convert energy stored in food to energy that the cell can use. which of the cell's organelles has stopped working? a.the mitochondria b.the nucleus c.the vacuoles d.the endoplasmic reticulum

What is the molarity of the solution produced when 145 g of nacl is dissolved in sufficient water to prepare 2.75 l of solution?