IGCSE Sciences - Planning experiment, Exams of Chemistry

Hope this helps!~ Upvote so others can see this! All the best for you upcoming examinations! <3

Typology: Exams

2022/2023

Available from 05/05/2023

FATTOUH
FATTOUH 🇺🇸

4.3

(3)

766 documents

1 / 14

Toggle sidebar

This page cannot be seen from the preview

Don't miss anything!

bg1
Dr. Mohamed Gamal
3. Rusting
Q1.
Steps:
Get an iron nail with 2g mass
Get a test-tube and add 10 cm3 of tap water
Place the iron nail in the test-tube and leave it to rust
Observe the nail after a week
Repeat the experiment using the other two water samples using
same volume of water and same surface area of nails and leave for
same time.
compare the mass of the rusted nails and the largest change in mass
will have rusted the fastest
Q2.
Steps:
Get a steel nail with 2g mass
Add 10 cm3 of water and 5 cm3 of corrosion inhibitor R to a test-tube
Place the nail in the test-tube and leave it for a week to rust
Repeat this process with the inhibitors Q and S using same volumes
and duration (1 week) and same mass and surface area of the nail
Compare the results, the nail with the least change in mass will have
the strongest corrosion inhibitor.
pf3
pf4
pf5
pf8
pf9
pfa
pfd
pfe

Partial preview of the text

Download IGCSE Sciences - Planning experiment and more Exams Chemistry in PDF only on Docsity!

3. Rusting

Q1.

Steps:

  • Get an iron nail with 2g mass
  • Get a test-tube and add 10 cm^3 of tap water
  • Place the iron nail in the test-tube and leave it to rust
  • Observe the nail after a week
  • Repeat the experiment using the other two water samples using same volume of water and same surface area of nails and leave for same time.
  • compare the mass of the rusted nails and the largest change in mass will have rusted the fastest

Q2.

Steps:

  • Get a steel nail with 2g mass
  • Add 10 cm^3 of water and 5 cm^3 of corrosion inhibitor R to a test-tube
  • Place the nail in the test-tube and leave it for a week to rust
  • Repeat this process with the inhibitors Q and S using same volumes and duration (1 week) and same mass and surface area of the nail
  • Compare the results, the nail with the least change in mass will have the strongest corrosion inhibitor.

5. Preparation of salts.

Q1.

  • Add dilute sulfuric acid to a beaker
  • Add excess magnesium oxide to the beaker
  • Heat the beaker on a Bunsen burner
  • Filter the excess unreacted magnesium oxide
  • Heat the solution (filtrate) till crystallization point , check for crystallization point by using a glass rod
  • Leave solution to cool
  • Filter crystals
  • Dry crystals gently using filter paper

6. Extraction of metals.

Q1.

Steps:

  • Crush malachite using mortar and pestle
  • Add nitric acid to the malachite
  • Solution is formed

1. Comparison between production of energy :

Q1:

Steps:

  • Add the first fuel (diesel) to spirit burner
  • Measure the Initial temperature of water
  • Start burn for certain time
  • Stop the reaction, Then Measure the Final temperature of water
  • Repeat experiment using the second fuel (biodiesel)
  • For fair comparison, use same volume of fuel/same volume of

water/same time interval/same distance between tube and

burner/same initial temperature

  • Fuel with greater temperature difference produce more energy.

Ideas for paper 6

(last question)

Q2 :

Steps:

  • Hold the test tube of water with stand & Put the peanuts below it
  • Measure the Initial temperature of water
  • Start burning for certain time
  • Stop the reaction, then Measure the Final temperature of water
  • Repeat the experiment with the other nuts (Brazil & hazel nuts)
  • For fair comparison, use same mass of nuts / same volume of water/ same distance between test tube and the nuts/ same initial temperature
  • Nuts with greater difference in temperature produce more energy. Q3:

Steps:

  • Use equal mass of coal , Crush it with mortar & pestle
  • Put the coal in fume cupboard and start heating
  • Pass it through potassium manganate(VII)
  • Then Measure Time taken for purple to become colourless
  • Repeat experiment with the second type of coal using same mass and same surface area
  • Coal with less time taken for colour to disappear produce most Sulfur dioxide.

Steps:

  • By Filteration
  • Sand in residue
  • Wash the residue & dry between two filter papers

4. How to determine:

Q1: The Concentraton:-

Steps:

  • Add 25 cm^3 of kleen up in flask
  • Add nitric acid to the burette
  • Add indicator to conical flask
  • Start adding acid to the flask until indicator change colour to neutral
  • Record volume of acid used
  • Then calculate the concentration:

No of moles of Ammonia = No of moles of nitric acid

C x V = C x V

Q2: The percentage :

Steps:

  • Weight the mixture (100g)
  • Add excess sulfuric acid
  • Warm and stir
  • Filter , wash and dry the residue (carbon) between filter paper
  • Then the mass of residue
  • Calculate the percentage :

100 – carbon mass

7. How to prepare an indicator :

Q1:

Steps :

  • Crush the berries with pestle and mortar
  • Add water and mix
  • Then filter off , the filtrate is the solution of an indicator

Q2:

Steps :

  • Add the indicator to hydrochloric acid
  • Add the indicator to sodium hydroxide
  • Colours must be different for each solution

11. Differentiate between 2 solutions :

Q1: Type of the solutions Steps :

  • Add x cm^3 of solution H to boiling tube
  • Add manganese(IV) oxide
  • Connect gas syringe to collect the gas
  • Start heating for certain time
  • Measure total volume of gas produced
  • Repeat the experiment with solution J using same volume of hydrogen peroxide and same mass of manganese(IV) oxide
  • Finally, the solution that produces large volume of oxygen gas is the new one. Q2: Strength of the solution: Steps :
  • Add 25 cm^3 of hydrochloric acid to a clean conical flask
  • Add few drops of methyl orange indicator into the conical flask
  • Fill the burette with oven cleaner C and note the starting volume
  • Start titration until the colour change
  • Then stop adding oven cleaner C and note the volume added
  • Repeat the experiment using same volume of oven cleaner B and same volume and concentration of HCl

8 .Reactivity Series :

Q1:

Steps:

  • Use 10 cm^3 of hydrochloric acid in test tube.
  • Add zinc metal.
  • Count the number of bubbles
  • Repeat experiment with silver and tin using same mass and surface area of metals.
  • The metal with the highest bubbles is the most reactive.

2. Catalyst:

Q1:

Steps:

  • Use same volume and concentration of hydrogen peroxide.
  • Add copper oxide to hydrogen peroxide.
  • Measure the volume of gas produced per unit time using a gas syringe.
  • Then compare that to the volume of gas produced from hydrogen peroxide without adding copper oxide.
  • Compare volume of gas produced

Q2:

Steps:

  • Weigh the copper oxide before adding to the hydrogen peroxide.
  • After the reaction is done, filter the copper oxide from the solution.
  • Dry it using an oven (or between two filter papers)
  • Weigh its mass
  • Compare the final mass with the initial mass.

10. Electroplating :

Q1:

Steps:

  • Prepare a copper sulfate solution.
  • Set up a circuit and a source of electricity.
  • Clean the ring using sand paper.
  • Place the ring at the cathode.
  • Place the copper rod in the anode.
  • Switch on electricity.
  • Make sure the ring is being rotated.
  • Remove the ring after electroplating and wash it.