Calculate ΔHrxn for the following reaction: CaO(s)+CO2(g)→CaCO3(s)

Use the following reactions and given ΔH values:

Ca(s)+CO2(g)+12O2(g)→CaCO3(s), ΔH= -812.8 kJ
2Ca(s)+O2(g)→2CaO(s), ΔH= -1269.8 kJ

Express your answer using four significant figures.

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2points why do scientists need governmental funding? o a. government politicians ask all the important scientific questions. o b. scientists have to pay taxes to the government on the money they make. o c. the cost of doing scientific research can be very high. o d. the government is controlled by scientists. submit

Which step in naming unsaturated hydrocarbons is used for alkenes but not alkynes

Which element would mostly likely have an electron affinity measuring closest to zero