What is the % error if the theoretical value of the enthalpy of a reaction is 97 kJ and the experimental value is 67 kJ?  Do not include % sign.

A student mixed 50 ml of 1.0 M HCl and 50 ml of 1.0 M NaOH in a coffee cup calorimeter and calculated the molar enthalpy change of the acid-base neutralization reaction to be –54 kJ/mol.  He next tried the same experiment with 100 ml of 1.0 M HCl and 100 ml of 1.0 M NaOH. The calculated molar enthalpy change of reaction for his second trial was: –27 kJ/mol –54 kJ/mol –108 kJ/mol –216 kJ/mol none of these

When sulfuric acid dissolves in water, a great deal of heat is given off. The enthalpy change for this process is called the enthalpy of solution. To measure it, 175 g of water was placed in a coffee-cup calorimeter and chilled to 10.0°C. Then 49.0 g of pure sulfuric acid (H₂SO4(1)) also at 10.0°C, was added, and the mixture was quickly stirred with a thermometer. The temperature rose rapidly to 14.9°C. Calculate the energy released during the for the formation of this solution and the enthalpy of solution (in kilojoules per mole of H₂SO4). Assume that the mass of solution = mass water + sulfuric acid. Assume that that the specific heat capacity of all solutions is 4.184 J/g °C.

Why are fractional coefficients permitted in a balanced thermochemical equation? Fractional coefficients are permitted in order to have the smallest possible set of coefficients for a given reaction. Fractional coefficients are permitted because the enthalpy change for the reaction is dependent on the amount of matter present. Fractional coefficients are permitted because the enthalpy change for the reaction is independent of the amount of matter present. In thermochemical reactions, only small amounts of matter are considered. O If fractional coefficients were not used, the scale of the reaction would be excessively large.

nuraipy changes in chemical reactions Read through pages 18-20 in your laboratory manual for information on how to calculate the enthalpy change in a solution. Part A - Calculating ms In a calorimetry experiment 5.6 g of potassium hydroxide is dissolved in 400 mL water in a thermos flask. The temperature increase in the solution is 7 °C. The effective mass of the glass in the thermos flask (mcal) is 0.040 kg. The heat capacity of the solution (Cs) is 4.04 kJkg-¹K-1¹. The heat capacity of the calorimeter (Ccal) is 0.387 kJkg-¹K-1. Remember to enter your answer using the specified number of significant figures, but keep the entire number in your calculator for use in further calculations. Calculate the total mass of solution in kilograms (ms) Give your answer to four significant figures. ▾ View Available Hint(s) Hint 1. Calculating ms mg = mass water (kg) + mass solute (kg) —| ΑΣΦ Submit Request Answer ? kg < Pear 10

If 0.0181 moles reacted, and 372.8 J of heat were absorbed by the reaction in a coffee cup calorimeter, what is the enthalpy of the reaction in kJ/mol?

When 1.42 g of iron reacts with 1.80 g of chlorine, 3.22 g of iron(II) chloride (FeCl2, molar mass = 126.75 g/mol) and 6.8 kJ of heat is produced. What is the enthalpy change for the reaction when 1 mole of iron(II) chloride is produced? round to sig figs

calculate the standard enthalpy change (in kJ/mol) for each of the following reactions. (a) 2 Na(s) + I2(g) → 2 NaI(s)  _______________kJ/mol (b) Cr2O3(s) + 3 H2(g) → 2 Cr(s) + 3 H2O(l)  ___________kJ/mol (c) 2 KOH(s) + CO2(g) → K2CO3(s) + H2O(g) _________________ kJ/mol (d) Na(s) + O2(g) → NaO2(s)  _____________kJ/mol

2 ·als NaOH, H ethanol heat

22) Given the following reactions 2NO → N2 + 02 2NO+O2 → 2NO2 the enthalpy of the reaction of nitrogen with oxygen to produce nitrogen dioxide N2+202 → 2NO2 is A. -68 B. 68 C. -292 D.) 292 AH = -180 kJ AH = -112 kJ kJ.