Question

Classwork: Ch. 6 Thermodynamics 1. A sample of nitrogen expands in volume from 1.6 L to 5.4 L at constant temperature. What is the work in joules if the gas expands (a) against a vacuum and (b) against a constant pressure of 3.7 atm? 2. How much heat is evolved (given off) when 266 g of white phosphorus (P) burn in air? P, (s) + 50,0) - P.O.(s) AH--3013 kJ/mol 3. Benzene (CH) burns in oxygen to produce carbon dioxide and liquid water. Calculate the standard enthalpy of the reaction as shown and the heat given off by burning one mole of benzene. The standard enthalpy of formation of benzene is 49.04 kJ/mol 4. Calculate the standard enthalpy of formation of CS. (1) given that: Cgraphite) + O2(e) > CO2(g) AH--393.5 kJ/mol S(thombic) +O:()-> SO() AH = -296.1 kJ/mol CS.(+30:() - CO2(g) + 250>() AH --1072 kJ/mol 5. How much heat is given off when an 869 giron bar cools from 94°C to 5°C? s of Fe = 0.4441/( C) 6. A 50.0 mL sample of 0.250 M HCl at 19.50°C is added to 50.0 mL of 0.250 M NaOH at the same temp. in a calorimeter. After mixing the temp. rises to 21.21 °C. Calculate the heat of this reaction and give the value of AH for the chemical reaction (as written): HCI (aq) + NaOH(aq) -- NaCl (aq) + H20 AH = ?

Answer 1

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