Given the following reactions CaCO3 (s) → CaO (s) + CO2 (g) ΔH = 178.1 kJ C (s, graphite) + O2(g) → CO2(g) ΔH = -393.5 kJ the enthalpy of the reaction CaCO3 (s) → CaO (s) + C (s, graphite) + O2 (g) is kJ. A -215.4
B 215.4
C 7.01 × 104
D 571.6
E -571.6

answer: the figure is attached herewith.

step-by-step explanation:   we are given to sketch a unit circle and label the terminal points corresponding to

in the attached figure, we have drawn a unit circle, with centre at o(0,0) and radius 1 unit. we have labelled the points a, b, c, d and e corresponding to the angles below

∠aox = 60°,

∠box = 120°,

∠cox = 180°,

∠dox = 240°,

∠eox = 300°.

and the coordinates are a(0.5,1), b(-0.5,1), c(-1,0), d(-0.5,-1) and e(0.5,-1).

thus, the answer is complete.

answer is: c. the experiment shows that the red substance experienced a chemical change.

this is chemical change (chemical reaction), because two new substances are formed (metalig liquid and gas), the atoms are rearranged and the reaction is followed by an energy change.

this is example of chemical decomposition.

chemical decomposition (analysis) is the separation of a single chemical compound into its two or more elemental parts or to simpler compounds.  

chemical decomposition is opposite of chemical synthesis.

i believe it is a.) released into

explanation: