A 488.3 gram sample of an unknown substance (MM = 92.41 g/mol) is heated from -23.1 °C to 51.8 °C. (heat capacity of solid = 2.96 J/g･°C; heat capacity of liquid = 1.75 J/g･°C; ∆Hfusion = 8.04 kJ/mol; Tfinal = 17.6 °C) A)How much energy (in kJ) is absorbed/released to heat the solid?
B)How much energy (in kJ) is absorbed/released to melt the solid?
C) How much energy (in kJ) is absorbed/released to heat the liquid?
D)What is the total amount of energy that must be absorbed/released for the entire process?

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.

Determine the empirical formula for succinic acid that is composed of 40.60% carbon, 5.18% hydrogen, and 54.22% oxygen.

Ais a mountain created from eruptions of lava, ash, rocks, and hot gases.