University:
Missouri State University
Course:
CHM 160 | General Chemistry I
Academic year:

2022
Views:

433

Pages:

11
Author:

Carissa Thomas

1. (5.4) Enthalpies of Reaction 2. Thermochemical Equations 3. (5.5) Calorimetry The change in enthalpy that accompanies a chemical reaction is known as the "enthalpy of reaction" or "heat of reaction." (ΔΗrxn). Thermochemical equation is a chemical equation that includes AH. 2H2(g) + O2(g) → 2H2O(g) AH = -483.6 kJ 2:1:2:483.6k 2Hz(g) Ozg) 2H2O+483.6k5 D 20 (9) 220g) D2Hzcast Ozcg) ΔΗ=+483.65J (g) H2(g)+ ½ O2(g) △H=+241.8KJ Page 206. #51. a) What is the specific heat of liquid water? 4.18 b) What is the molar heat capacity of liquid water? 4.18J x 180gH20 I mol H20 = 75.2 Mol-C c) What is the heat capacity of 185 g of liquid water? 185g420 4.18 J = 773 d) How many kJ of heat are needed to raise the temperature of 10.00 kg of liquid water from 24.6°C to 46.2°C? 8=10,000) (4.18) (21.68) = 902,880 J = 903 kJ The change in enthalpy that accompanies a chemical reaction is known as the "enthalpy of reaction" or "heat of reaction." (ΔΗrxn). Thermochemical equation is a chemical equation that includes AH. 2H2(g) + O2(g) → 2H2O(g) ∆H = -483.6 kJ 2H₂(3) + O2(3)→2420(9) + 483.6 kJ 2H2O(9) 2H2(g) + O2(g) AH= +483.6KJ ७) H2013) H2(g) + 202(3) ΔΗ=+241.8 κα Calorimetry is the measure of heat flow. q = m C At ∆H = q (at constant pressure) m = mass (g) C= specific heat capacity (J/g°C or J/gK) At change in temperature (°C or K) Calorimeter is a device used to measure heat flow. Cork per Tsuten C = specific heat capacity (J/g°C or J/gK). The amount of heat required to raise 1 g of substance 1°C. molar heat capacity - the amount of heat required to raise 1 mole of substance 1°C. (J/mol °C) heat capacity - the amount of heat required to raise an amount of substance 1°C. (J/°C) Solid iron has a specific heat of 0.45 J/g°C. What is iron's molar heat capacity? What is the heat capacity of 10.0 g of Fe? Solid iron has a specific heat of 0.45 J/g°C. What is iron's molar heat capacity? What is the heat capacity of 10.0 g of Fe? C= 45J 9.C 55.8 Fe gre Imol Fe 10.0gfex 450 X .45J mol 25.1J mol. C = 4.5 =