Calculate ΔE, and determine whether the process is endothermic or exothermic for the following cases. a. Calculate ΔE for a system that absorbs 661.0 kJ of heat from its surroundings and does 277.0 kJ of work on its surroundings.
b. Calculate ΔE, if q= 1.60 kJ and w= -657 J . Express your answer using two significant figures.
c. Calculate ΔE, if the system releases 56.5 kJ of heat while doing 13.0 kJ of work on the surroundings. Express your answer using three significant figures.

Straightforward questions answered in the powerpoint slidesreaction: heating the starting materials under refluxwhat does it mean to heat under reflux? why do we choose water as the reflux solvent? what are boiling chips used for? why do we put a condenser on top of the reaction? why do we add heat and let the reaction stir for 30 minutes? why do we add sulfuric acid to the reaction after it cools as opposed to when it’s still hot? separation: filtration of precipitatewhy don’t we do an aqueous and organic extraction in the separatory funnel? why do you rinse the salicylic acid on the filter with ice cold water? purification: recrystallization of salicylic acid (no hot filtration needed)what is the difference in the amount of room temperature water vs. boiling water needed to dissolve the salicylic acid (assume a 1.2 gram yield of salicylic acid)? remember, in the lab if you need x ml of boiling water to dissolve a solid, then you should add a little more (definitely no more than 1.5 times the theoretical amount) to ensure it doesn’t recrystallize prematurely.analysis: melting point of salicylic acidwhat can you conclude if the melting point of the salicylic acid you just synthesized is 152-155oc and the 1: 1 mix of your product and “synthetic” salicylic acid is 151-154oc?

Write the chemical formula for a compound that is made of an element from group 1 and an element from group 17

Find the number of moles of argon in 364g of argon.