• Join over 1.2 million students every month
  • Accelerate your learning by 29%
  • Unlimited access from just £6.99 per month

Research Question: How does the solubility of potassium nitrate change with respect to the change in temperature by 20C keeping the pressure and the nature of the solute and solvent constant?

Extracts from this document...


CHEMISTRY LABORATORY REPORT To investigate the solubility of ionic compounds. Design Nikita Bansal B.D.Somani International School Chemistry Standard Level Candidate Number- 002602015 Session: May 2010 Aim: To investigate the solubility of Ionic Compounds Research Question: How does the solubility of potassium nitrate change with respect to the change in temperature by 20�C keeping the pressure and the nature of the solute and solvent constant? Hypothesis: An Ionic Compound is a chemical compound in which ions are held together in a lattice structure by ionic bonds. Ionic bonding occurs between elements that have a large difference in their electronegativities. In this bonding, a metal loses electrons to form a positively charged ion (cation) and a non- metal gains an electron to forma positively charged ion (anion). The compounds formed due to ionic bonding are held together due to a strong electrostatic force of attraction. Solubility is a result of an interaction between polar water molecules and the ions which make up a crystal. ...read more.


The temperature ranges from 20 to 100c and thus we can see that the solubility increases. The above diagrams show that an increase in temperature will lead to an increase in the solubility of potassium nitrate. The solubility of solutes is dependent on temperature. When a solid dissolves in a liquid, a change in the physical state of the solid takes place. Heat is required to break the bonds holding the molecules in the solid together. At the same time, heat is given off during the formation of new solute -- solvent bonds. If the heat given off in the dissolving reaction is less than the heat required to break apart the solid, the net dissolving reaction is endothermic (energy required). The addition of more heat facilitates the dissolving reaction by providing energy to break bonds in the solid. This is the most common situation where an increase in temperature produces an increase in solubility for solids. This is what will occur in the heating of the potassium nitrate and therefore the solubility will increase. ...read more.


7. After the crystallization temperature has been recorded, put the test tube back into the water bath and warm the solution until all of the crystals have re dissolved. Repeat the cooling procedure to check the crystallization temperature. The two readings should be within 1 degree of each other. If the two readings do not agree within 1 degree, re warm the solution in the water bath, cool it, and continue until satisfactory agreement is obtained. 8. Record sample mass and then record the experimental temperature next to it. 9. Repeat the experiment two to three times to ensure accuracy. Precautions: - Handle hot equipment and solutions cautiously. - The thermometer bulb is fragile; handle gently Apparatus 1. 1 0.5 dm3 beaker 2. 1 iron ring 3. 1 wire gauze 4. 0.3dm3 tap water 5. 5g Potassium Nitrate 6. 2 Test tubes along with test tube holder 7. Stirring wire 8. Thermometer 9. Bunsen Burner 10. Water Bath Data Table KNO3 Solubility Temperature 20 40 60 80 100 ?? ?? ?? ?? Nikita Bansal Chemistry Standard Level ...read more.

The above preview is unformatted text

This student written piece of work is one of many that can be found in our International Baccalaureate Chemistry section.

Found what you're looking for?

  • Start learning 29% faster today
  • 150,000+ documents available
  • Just £6.99 a month

Not the one? Search for your essay title...
  • Join over 1.2 million students every month
  • Accelerate your learning by 29%
  • Unlimited access from just £6.99 per month

See related essaysSee related essays

Related International Baccalaureate Chemistry essays

  1. Water of crystallization of BaCl2.xH2O

    processing: Equation: BaCl2.xH2O --> BaCl2 + xH2O As seen from the equation, the number of water molecules in the crystallized BaCl2 is the number of moles of water lost. Therefore, once we find the ratio of the number of moles of anhydrous BaCl2 and the number of moles of water

  2. Determination of potassium hydrogen carbonate into potassium carbonate

    Hence 0.4 + 0.4 = 0.8% For KHCO3: Trial 1: (0.010/3.455) X 100 = 0.3% Trial 2: (0.010/3.665) X 100 = 0.3% Therefore the overall uncertainty equals 0.3 + 0.3 = 0.6% The moles of each species are required to be calculated.

  1. Research question - How many molecules are there in a liquid drop?

    These errors were made right and taking trials before the experiment ensured we had a more precise, accurate and relevant experiment. We also decided to take the mass as the dependent variable, instead of volume, as we were provided with a measuring scale which was much more accurate (� 0.01 g)

  2. Faraday's Constant

    Every five minutes, the power pack was turned off and the cathode removed 4. It was washed with distilled water into a separate beaker to eliminate any remains of the copper (II) sulphate solution 5. The cathode was then dried and weighed on a 3-decimal-placed balance to measure the addition in mass 6.

  1. IB chemistry revision notes

    Charge of ions: the higher the charge the greater the attraction between them and thus they require more energy to separate. 3. Type of lattice structure: packing ions determines how close, on average, the ions are to each other. o Brittle--> when a force is applied the lattice varies its arrangement, provoking repulsion between the ions.

  2. Free essay

    Vitamin C in Fruit Juices

    Final Burette Volume (mL) Iodine Used (mL) Vitamin C Standard Solution (10.0mL) 1 0 33.81 33.81 2 0 33.83 33.83 3 0 33.68 33.68 4 0 33.80 33.80 Average 33.78 TABLE 2 - Titration Data Substance Trail Initial Burette Volume (mL)

  1. IA Lab report solubility

    The uncertainty of g salt in the solution is � 0.02, as two uncertainties, each of � 0.01 were subtracted. The uncertainty of the solubility will be different dependent on which values we use, but it can be expressed in a general formula: Using the above model, the following values were found: KCl Weight in beaker (g � 0.01)

  2. Research into the production of Nitrate Fertillisers.

    The ammonium fraction is taken up by roots or gradually converted to nitrate by soil microorganisms. Many vegetable growers prefer an immediately available nitrate source of plant nutrition and use ammonium nitrate. It is popular for pasture and hay fertilization since it is less susceptible to volatilization losses than urea-based fertilizers when left on the soil surface.

  • Over 160,000 pieces
    of student written work
  • Annotated by
    experienced teachers
  • Ideas and feedback to
    improve your own work