A constant-volume calorimeter was calibrated by carrying out a reaction known to release 1.18 kJ of heat in 0.500 L of so In the calorimeter (q = -1.18 kJ), resulting in a temperature rise of 2.10 C. In a subsequent experiment, 250.0 mL of 0.40 M HClO₂ (aq) and 250.0 mL of 0.40 M NaOH(aq) were mixed in the same calorimeter and the temperature rose by 5.70 C. What is the change in the internal energy of the reaction mixture as a result of the neutralization reaction?

The following reaction: 2NaOH(aq) + H2SO4(aq) → Na2SO4(aq) + 2H2O(l)was studied in a coffee cup calorimeter. In the experiment, 100. mL portions each of 1.00 M aqueous NaOH and H2SO4, each at 24.0°C were mixed. The maximum temperature achieved was 30.6°C. Neglect the heat capacity of the cup and the thermometer, and assume the solution of products has a density of 1.00 g/mL and a specific heat capacity of 4.18 J/g K.What is the heat of reaction, (Delta)Hrxn, for the reaction as written in kJ?

In Part B of the experiment, a student mixes 30.0 mL of 1.1 M HC1(aq) with 30.0 mL of 1.000 M NaOH(aq) in a well-insultated calorimeter and observes that the temperature of the solution increases by 5.75 °C. These are similar conditions as the previous two problems. How many moles of water are formed? number of moles of water = mol

A chemist measures the enthalpy change AH during the following reaction: 4 Fe(s) + 3 02(g)→2 Fe,O3(s) AH =-320. kJ Use this information to complete the table below. Round each of your answers to the nearest kJ/mol. reaction ΔΗ x10 Fe(s) + 0,6) - Fe,0,(1) O kJ 2Fe,0; (s) – 4Fe(s) + 30, (3) O kJ 4Fe,0, (s) - 8Fe(s) + 60, (3)

5.00 × 10−2 mol KOH and an excess of hydrochloric acid are combined in 100.0 mL of water initially at 25.0 °C, leading to a final measured temperature of 31.1 °C. (a) What is the heat flow for the water in the calorimeter, qH2O, in Joules? (b) Assuming the calorimeter constant Ccal = 50.0 J °C , what is the heat flow for the calorimeter, qcal, in Joules? (c) What is the amount of heat given off by the reaction, qrxn, in Joules? (d) What is the molar enthalpy of the neutralization reaction (shown below) as measured in the calorimeter, ∆H◦ rxn in kilojoules per mole? H3O + (aq) + OH– (aq) → 2H2O (l)

A chemist measures the enthalpy change AH during the following reaction: COCL,(9) + 4 NH,(g)–+cO(NH,),(s) + 2 NH,Cl(s) AH=-559. kJ Use this information to complete the table below. Round each of your answers to the neare reaction AH co(NH,),(-) + NH,CI(3) - coC, () + 2NH, (2) 3coCI, (3) + 12NH, (3) - 3c0(NH,), (-) + 6NH,CI(s) co(NH,),() + 2NH,C1(«) → COCI, (3) + 4NH, (2) Explanation Check MacBook Air 20 F1 F3 F4 F5 F6 F @ & くC

(1) What are the thermodynamic quantities of a system that affect the amount and sign of the internal energy change of a system? (ii) Consider the process represented by the following chemical equation: H,O() NH,NO3(s)· NH,"(aq) + NO5(aq) AH = +28.05 kJ/mol Using correct thermodynamic terminology, explain the sign of A Tsurroundings for this process.