Concept explainers
(a)
Interpretation:
The equation and value of
Concept introduction:
According to Hess’s law, if addition of two reactions takes place to get the overall reaction, the value of
(b)
Interpretation:
The arrow corresponding to the step and the one corresponding to the net reaction needs to be determined.
Concept introduction:
According to Hess’s law, if addition of two reactions takes place to get the overall reaction, the value of
(c)
Interpretation:
The substance represented by each energy level needs to be determined.
Concept introduction:
According to Hess’s law, if addition of two reactions takes place to get the overall reaction, the value of
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CHEMISTRY-MOD.MASTERING (18W)
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- Alloys When a 58.8-g piece of hot alloy is placed in125 g of cold water in a calorimeter, the temperature ofthe alloy decreases by 106.1°C, while the temperature ofthe water increases by 10.5°C. What is the specific heat ofthe alloy?arrow_forwardUsing the data in Appendix G, calculate the standard enthalpy change for each of the following reactions: (a) Si(s)+2F2(g)SiF4(g) (b) 2C(s)+2H2(g)+O2(g)CH3CO2H(l) (c) CH4(g)+N2(g)HCN(g)+NH3(g) ; (d) CS2(g)+3Cl2(g)CCl4(g)+S2Cl2(g)arrow_forwardWhen calcium carbonate, CaCO3 (the major constituent of limestone and seashells), is heated, it decomposes to calcium oxide (quicklime). CaCO3(s)CaO(s)+CO2(g);H=177.9kJ How much heat is required to decompose 21.3 g of calcium carbonate?arrow_forward
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