Planning 1 Starter… H/W… Compare your findings with the people around you and discuss. H/W… Carry out a risk assessment and plan how you will carry out your trials Due next week’s 1st single lesson Review question maybe using a mind map on a white board

5 week plan single lessons Week 1 – Briefing Week 2 – Planning Week 3 – Planning Week 4 – Trials for CPAC Week 5 – Rates CPAC If you miss a session you MUST download the PowerPoint from the shared area and collect associated materials, this is your responsibility. You must complete all homeworks or you will not be allowed onto Y13 chemistry. No excuses

Task Magnesium ribbon 2 moldm-3 HCl Access to general lab apparatus including: stopwatches, beakers, volumetric flasks, glass rods, You will vary the concentration of the HCl

Risk assessment List all the chemicals you intend to use or make. Give the approximate quantities in each case, and state whether the substance will be in pure form or in solution. If in solution, at what concentration? For each substance, identify the hazards. State whether it is: flammable, harmful, irritant , oxidizing, explosive, toxic, corrosive , radioactive If there is a maximum exposure limit, state this also. Use the references listed below to help you. For example, you could use suppliers’ catalogues to identify the hazardous chemicals and then look up the conditions of use on the Hazcards. Identify any hazards that may arise during the operations you will carry out – for example, there may be a highly exothermic reaction when two chemicals are mixed. Give the safety precautions you will use when handling each of the hazardous substances, or carrying out hazardous operations. Make sure that you include your completed Risk Assessment in the Planner form and discuss it with your teacher. Remember that if you change your plans you may need to change your Risk Assessment.

Trials Method Volume of HCl Concentration range Surface area Mg Cleaning the Mg Time / temp rise Aim of the trials if to get repeatable results. So each condition should be trialled 2-3 times and you want the results to be similar each time

YOU SHOULD MAKE UP 6-7 DIFFERENT CONCENTRATIONS Making up solutions YOU SHOULD MAKE UP 6-7 DIFFERENT CONCENTRATIONS Concentration Volume 2 mol acid / cm3 Volume of water / cm3 2.0 50 1.5 37.5 12.5 1.0 25 0.5

Ensure that you know that your HCl is in excess Plenary Ensure that you know that your HCl is in excess How will you do this?