For each mass of magnesium, the temperature increase is smaller than expected. Give one reason for this.
State two changes that can be made to the apparatus so that the temperature rise for each mass of magnesium is nearer the expected value.
Use the thermometer values to fill in the table.
Which evidence in the table indicates that the reaction is exothermic?
Plot the temperature rise against the mass of magnesium on the grid. Draw one straight line through the first four points. Draw another straight line through the last three points, then extend both lines so that they intersect.
What temperature rise is obtained when $0.35\,\text{g}$ of magnesium is used?
What is the highest temperature when $0.15\,\text{g}$ of magnesium is used?
What mass of magnesium gives a highest temperature of $26.0\,^{\circ}\text{C}$?
What is the smallest mass of magnesium that reacts with all of the hydrochloric acid?
Use your answer to (e)(iv) to calculate how many moles of magnesium react with $100\,\text{cm}^3$ of dilute hydrochloric acid. [$A_r$: Mg, 24]
Magnesium reacts with dilute hydrochloric acid. $\text{Mg} + 2\text{HCl} \rightarrow \text{MgCl}_2 + \text{H}_2$ Calculate the concentration, in $\text{mol dm}^{-3}$, of the hydrochloric acid.