A sample of solid biphenyl weighing 0.5260 g was ignited in a bomb calorimeter initially at 25 °C, producing a temperature rise of 1.910 K. Assuming a constant volume, calculate the AH of combustion of biphenyl. To properly determine the standard enthalpy of combustion for the solid biphenyl, the calorimeter was first calibrated. A 0.7750 g sample of benzoic acid (C6H3COOH, MW 122.1 g/mol)) was ignited under identical conditions and produced a temperature rise of 1.940 K. For benzoic acid, the internal energy combustion at constant volume, AU, is known to be -3226 kJ/mol. Calculate the calorimeter constant, in kJ/K.

A 1.00 g sample of MgCl2 produced a 10.00 °C increased in a calorimeter charged with 40.0mL of deionized water. The specific heat of MgCl2 is 0.750 J/°C·g. What is the value of DsH for MgCl2?

22.68g of an unknown sample, with a molar mass of 53.90g/mol, reacts with excess reagents inside a simple calorimeter. The outside of the calorimeter is made of an aluminum cup with a mass of 81.0g. There is 136g of water inside the calorimeter. The temperature of the entire calorimeter increases from 20.0°C to 22.9°C. What is the molar enthalpy of reaction, in kJ/mol, with respect to the unknown?

When a 3.00 g sample of RbBr is dissolved in water in a calorimeter that has a total heat capacity of 1.89 kJ · K¯¹, the temperature decreases by 0.210 K. Calculate the molar heat of solution of RbBr. AH S = soln kJ/mol

Two student chemists measured 25.0mL of 1.00 M NaOH in separate calorimeters as in the experimental procedure, Part B. Student 1 added 25.0mL of 1.10 M HCl in his solution of NaOH. Student 2 added 22.7mL of 1.10 M HCl in his NaOH solution. Each student recorded the temperature change and calculated the enthalpy of neutralization. Complete the following table to assist in answering the below questions. NOTE: Limiting reactant needs to be identified to calculate the enthalpy of neutralization. Student 1   Moles of NaOH              _________   Moles of HCl added       _________   Limiting reactant            _________   Moles of H2O produced _________   Mass of final mixture     _________     Student 2   Moles of NaOH              _________   Moles of HCl added       _________   Limiting reactant            _________   Moles of H2O produced _________   Mass of final mixture     _________     Explain why and how (higher or lower) the temperature will be different for the two…

Calculate the molar enthalpy for dissolving 25g of NaClin 100g of water inside a calorimeter. The calorimeter heat capacity is 500 J/c. The initial temperature is 25C and the final temperature is 26.5 C

Measurements show that the energy of a mixture of gaseous reactants decreases by 209. kJ during a certain chemical reaction, which is carried out at a constant pressure. Furthermore, by carefully monitoring the volume change it is determined that -104. kJ of work is done on the mixture during the reaction. Calculate the change in enthalpy of the gas mixture during the reaction. Be sure your answer has the correct number of significant digits. Is the reaction exothermic or endothermic? O exothermic O endothermic X

When 10.00 grams of cesium bromate is dissolved in 42.0 grams of water initially at a temperature of 25.00 ºC, the temperature of the solution decreases to 16.11 ºC. Calculate ΔHº for the reaction below in kJ/mol.[You may assume that the reaction takes place inside a perfect calorimeter and that the specific heat capacity of the solution formed is the same as for pure water.Calculate ΔHº for the reaction below in kJ/mol.CsBrO3 (s) ➝ Cs+ (aq) + BrO3 – (aq)       ΔHº= ?

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A 50.0 mL sample of a 1.00 MM solution of CuSO4CuSO4 is mixed with 50.0 mL of 2.00 MM KOHKOH in a calorimeter. The temperature of both solutions was 24.6 oCoC  before mixing and 32.8 oCoC  after mixing. The heat capacity of the calorimeter is 12.1 J/K.  From these data, calculate ΔHΔH for the process: CuSO4(1M)+2KOH(2M)→Cu(OH)2(s)+K2SO4(0.5M)CuSO4(1M)+2KOH(2M)→Cu(OH)2(s)+K2SO4(0.5M) Assume that the specific heat and density of the solution after mixing are the same as those of pure water and that the volumes are additive.