Chemical testing for Ions OCR SCIENCE – UNIT 1 BEST PRACTICE Chemical testing for Ions Prior learning Chemicals can react together and change colour Key words React, precipitate, colour change, identify, Cations, Anions

OCR SCIENCE – UNIT 1 BEST PRACTICE I am learning to: identify cations and anions in different solutions by their colour change I will be successful if I can: Describe the term cation and anion and explain the test to be carried out Carry out a practical activity safely (having completed a risk assessment) to confirm the presence of different cations an anions Complete a table to show results of practical tests Conclude, Evaluate and comment on reliability of the test Outcome: I can identify unknown ions in a given solution. TO ACHIEVE A MERIT: Add DETAIL to your report by explaining what is happening in each step using the guidance sheets. Relate the results of the test back to the scenario of students becoming ill having played on the playing fields. Complete an aim, prediction and method in handwritten form to add to your testing notes. Any of these can be completed at home or with Ms C’s help at break, lunch or after school.

Introduction: what are ions? I am learning to:identify cations and anions in different solutions by their colour change Introduction: what are ions? Ions are charged particles. Positively charged particles are called CATIONS (because they are attracted to the negative electrode called the cathode which are usually metals) Negative Ions are called ANIONS because they are attracted to the anode these are usually non-metals CuSO4 Cu 2+ SO4-

I am learning to:identify cations and anions in different solutions by their colour change Reference Ion Test Result Chloride Add Silver nitrate Solution White precipitate Sulphate Add acidified Barium chloride solution Carbonate Add dilute acid and test gas with limewater Milky white precipitate Copper (Cu++) Add Sodium hydroxide solution Blue precipitate Iron Brown precipitate

I am learning to:identify cations and anions in different solutions by their colour change Reference Copper Cations Sodium hydroxide Iron Cations

I am learning to:identify cations and anions in different solutions by their colour change Reference Carbonate Anions Acid Chloride Anions Silver Nitrate

I am learning to:identify cations and anions in different solutions by their colour change Reference Sulphate Anions Barium Chloride

I am learning to:identify cations and anions in different solutions by their colour change Risk Assessment Department: Science Room Number: R4 Brief summary of activity: Chemical tests for chlorides, sulphates and carbonates List hazardous procedures and the hazards) relating to them Procedure Using squirt bottles & glass Hazard Chemical in eye, broken glass cuts List the substances hazardous to health and the hazards) relating to them Substance chemicals Irritant, harmful and corrosive Risk and Safety phrases Wear goggles List who might be exposed to the hazard substance(s). (e.g. staff, students, visitors, cleaners) Staff & pupils Assessing the level of risk How severe is any injury or health effect likely to be? Medium How likely is exposure to the hazard? Medium High Medium Low Emergency Procedures (first aid actions, fire actions, spill action) Wash hands under cold water Wipe up any spills Brush up broken glass and put in glass bin Disposal requirements Technician to dispose of waste in prep room Date: Name: Signature: What is the overall level of risk? (Tick appropriate box – if risk is high further steps must be taken to minimum the risk of the procedure) x

I am learning to:identify cations and anions in different solutions by their colour change Results Test Samples   Add Silver nitrate solution Add acidified Barium chloride solution Add dilute acid and bubble gas through limewater Add Sodium hydroxide Sample ion A B C Soil Water

I am learning to:identify cations and anions in different solutions by their colour change Results Test Samples 1 2 3 water soil Add Silver nitrate solution yes X Yes Add acidified Barium chloride solution Add dilute acid and bubble gas through limewater Add Sodium hydroxide x Sample ion chloride sulphate copper Iron

Conclusion of findings I am learning to:identify cations and anions in different solutions by their colour change Conclusion of findings Conclusion of findings: ____________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________

I am learning to:identify cations and anions in different solutions by their colour change Reliability Do qualitative tests tell you how much of a substance is present? No, just if the substance is present 2. If the test substance is a mixture will one get clear results? No more than one result may show 3. Will the tests work if the substance is insoluble? no 4. Is there an amount of substance needed to get a positive test? Small amounts of each substance should work 5. Can your test substances be contaminated? Yes if clean pipettes are not used

Complete the associated worksheet on Chemical tests I am learning to: view samples using a microscope and test samples for metals using flame tests HOMEWORK Complete the associated worksheet on Chemical tests Approx. 10mins

OCR SCIENCE – UNIT 1 BEST PRACTICE I am learning to: identify cations and anions in different solutions by their colour change I will be successful if I can: Describe the term cation and anion Carry out a practical activity safely to confirm the presence of different cations an anions Complete a table to show results of practical tests Outcome: I can identify unknown ions in a given solution.

Summary – draw the colour changes of each test on plain paper I am learning to:identify cations and anions in different solutions by their colour change Summary – draw the colour changes of each test on plain paper Copper Cations Sodium hydroxide Iron Cations