![]() ![]() Do not let students discard residues into sinks. For disposal, provide a number of bowls (eg washing-up bowls) for the metal residues.Two spatula measures of each metal should be more than sufficient for each group. The metal samples can be provided in labelled plastic weighing boats, small beakers or watch glasses to prevent cross-contamination or wastage.A lid can be made by cutting a suitably-sized piece from a polystyrene ceiling tile and making a hole for the thermometer. It also prevents spillage if the student accidentally pokes the thermometer through the bottom of the polystyrene cup. A desirable, but not essential, addition is the provision of lids for the polystyrene cups. This provides a more stable reaction vessel. Typical expanded polystyrene cups fit snugly into 250 cm 3 squat form beakers.Hydrogen gas, H 2(g), (EXTREMELY FLAMMABLE) – see CLEAPSS Hazcard HC048.‘Powder’ refers to metal which is obviously ‘gritty’. Iron filings tend to be greasy and may need to be degreased with propanone (HIGHLY FLAMMABLE, IRRITANT – refer to CLEAPSS Hazcard HC085A) and dried before being provided to students. Powdered metals: aluminium, Al(s), copper, Cu(s), iron, Fe(s), magnesium, Mg(s) and zinc, Zn(s), (all HIGHLY FLAMMABLE) – see CLEAPSS Hazcards HC001A, HC026, HC055A, HC059A and HC107. The metals should be provided as powders or fine filings, or fine turnings, rather than fine powders or ‘dust’ (which are likely to be significantly oxidised).Dilute hydrochloric acid, HCl(aq), (IRRITANT) – see CLEAPSS Hazcard HC047a and CLEAPSS Recipe Book RB043. Each group of students can be provided with a 250 cm 3 beaker containing about 100 cm 3 of 2 M hydrochloric acid.Read our standard health and safety guidance.Aluminium powder (HIGHLY FLAMMABLE) (see note 4).Set of apparatus and chemicals as above.Large bowl for collecting the waste residues from the experiments (see note 8)įor the additional teacher-only demonstration.Powdered or finely-divided metals: magnesium, zinc, iron, copper (ALL HIGHLY FLAMMABLE) (see notes 4 and 7).Hydrochloric acid, approximately 2 M (IRRITANT) (see note 3 below).Beaker, 250 cm 3, to stand the polystyrene cup in for support.Polystyrene cup or cups (see note 6 below).Care should be taken to ensure that there are no naked flames or other sources of ignition in the laboratory. Hydrogen gas (EXTREMELY FLAMMABLE) is released in each reaction. An additional teacher-only demonstration of the reaction of aluminium powder with the acid could be included. Appropriate eye protection must be worn throughout the experiment and during any clearing up session.Īlternatively, the experiments could be done as demonstrations – perhaps making use of a flexicamera, digital temperature probe and projector, so that all the students can observe the reactions as well as view the temperature changes. This experiment is, therefore, best suited to students who can be trusted to behave sensibly. The hydrochloric acid used in this experiment is relatively concentrated, and the temperature rises can be quite significant. Try them with groups of students, or set them up as teacher demonstrations, to reinforce key ideas about energy changes during reactions, the reactivity series of the metals and the chemical behaviour of acids. In this set of experiments, students add powdered or finely-divided metals – including magnesium, zinc, iron and copper – to hydrochloric acid and measure the temperature changes. RSC Yusuf Hamied Inspirational Science Programme.Introductory maths for higher education.The physics of restoration and conservation.Reacts as a powder on very strong heating. Reacts readily when heated as iron filings. Yellow solid forms which changes to white on cooling. Reacts steadily when heated forming a yellow solid which changes to white on cooling. Reacts readily with strong heating as a powder. Slowly forms a surface oxide at room temperature Yellow/orange flame and white solid formed. Tarnishes when freshly cut at room temperature This table summarises the reactions of some metals in the reactivity series. ![]() We can examine the reactivity of metals by observing their reactions with oxygen, water, steam and whether it displaces other metals in displacement reactions.
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