chemistry

KCl(s) → K+(aq) + Cl‾ (aq)

Solid KCl dissolves as shown in the above equation. A 6.60 g sample of KCl was dissolved in 42.3 g of water. The initial temperature of the water was 21.90°C. After the compound dissolved, the temperature of the water was 10.20°C. Assume the heat was completely absorbed from the water and no heat was absorbed by the reaction container or the surroundings. Calculate the heat of solution of KCl in kJ/mol. The specific heat of water is 4.184 J/g·°C. (Do not take the added mass of the KCl into account when calculating q for the solution.)

  1. 👍
  2. 👎
  3. 👁
  1. q = mass H2O x specific heat H2O x (Tfinal-Tinitial)

    That gives you q/6.60g KCl = q/gram.
    To convert to q/mol it will be
    q/6.60 x (molar mass KCl/1 mol) = ? J/mol
    Convert to kJ/mol.

    1. 👍
    2. 👎
  2. q= 4.184(42.3)(10.2-21.9)
    = -2070.70 J
    -2070.70J/6.60g KCl = -313.74 J/g
    -313.74 J/g(74.55g/ 1 mol KCl)= -23389.32J/mol
    -23.4 kJ/mol
    Is this correct?

    1. 👍
    2. 👎

Respond to this Question

First Name

Your Response

Similar Questions

  1. Chemistry

    Which two solutions, when mixed together, will undergo a double replacement reaction and form a white, solid substance? 1. NaCl(aq) and LiNO3(aq) 2. KCl(aq) and AgNO3(aq) 3. KCl(aq) and LiCL(aq) 4. NaNO3(aq) and AgNO3(aq) I know

  2. Chemistry

    When solutions of KCl and Pb(NO3)2 are mixed, a precipitate forms. Which of the following is the balanced equation for the double replacement reaction that occurs? a. KCl(aq) + Pb(NO3)2 (aq) ¨ KNO3 (aq) + PbCl2 (s) b. KNO3 (aq)

  3. Chemistry

    a change in pressure would have the greatest effect on the solubility of a A. solid in a liquid B. gas in a liquid C.liquid in a liquid D.liquid in a solid in an aqueous solution of potassium chloride, the solute is A. Cl B. KCl

  4. Chemistry

    A KCl solution containing 42g of KCl per 100.0 g of water is cooled from 60 C to 0 C . What will happen during cooling?

  1. chemistry

    A student stated that the solubility of KCl at 20 degrees Celsius was 36 grams of KCl per 100 grams of solution. What is wrong with this statement?

  2. Chemistry

    What is the maximum mass(g) of KCL that can be added to 1.00L of a 0.0100 M lead(ii) chloride solution without causing any precipitation of PbCl2? Assume the additional KCl does not affect the volume of the solution. For, PbCl2,

  3. CHEMISTRY

    At what temperature do KCL and KNO3 have the same solubility If a saturated solution of KNO3 at 20.0 C is heated to 80.0 how much more could be dissolved? If a saturated solution of KCL at 90.0 C is colled to 30.0 C how much of

  4. AP Chemistry

    To prepare 1.000 kg of 5.5 percent by mass KCl (aq), one may dissolve a. 994.5 g KCl in 5.5 g of water b. 5.5 g KCl in 994.5 g of water c. 5.5 g KCl in 1000.0 g of water d. 55 g KCl in 945 g of water e. 55.0 g KCl in 1000.0 g of

  1. chem

    a solution is prepared with 3.26g kcl and water to make 25.0ml,of kcl,what is the %(m/V) of the kcl solution.

  2. University of Liberia , Chemistry

    How much kcl in grams is contained in 0.488l of 1.25m kcl solution?

  3. Physics

    Monochromatic x-rays (λ = 0.166 nm) from a nickel target are incident on a potassium chloride (KCl) crystal surface. The spacing between planes of atoms in KCl is 0.314 nm. At what angle (relative to the surface) should the beam

  4. science

    how much of a 0.225 M KCl solution contains 55.8g of KCl

You can view more similar questions or ask a new question.