你好 请帮我解释一下这道题---2 You will determine the enthalpy change, ΔH, for the reaction between magnesium and dilute sulfuric acid. The equation for the reaction is given below. Mg(s) + H₂SO₄(aq) → MgSO₄(aq) + H₂(g) FA 3 is 1.00 mol dm⁻³ sulfuric acid, H₂SO₄. two different coiled lengths of magnesium ribbon, Mg. (a) Method Read through the method before starting any practical work and prepare a table for your results in the space below. * Weigh the shorter piece of magnesium ribbon and record its mass. * Support the plastic cup in the 250 cm³ beaker. * Use the measuring cylinder to transfer 50 cm³ of FA 3 into the plastic cup. * Place the thermometer in the FA 3 in the plastic cup and record the initial temperature. * Add the shorter piece of magnesium ribbon into the plastic cup. Ensure that all of the magnesium is in contact with the acid. (Care: acid spray may occur.) * Stir the mixture and record the maximum temperature. * Empty and rinse the plastic cup. Shake out any excess water. * Repeat the experiment using the longer piece of magnesium ribbon and record all your data. Results [4] (b) Calculations Show your working and appropriate significant figures in the final answer to each step of your calculations. (i) Show by calculation that the sulfuric acid, FA 3, was used in excess in both experiments. (Aᵣ: Mg, 24.3)