A student investigated how concentration affects the rate of reaction between magnesium and hydrochloric acid. Figure 5 shows a gas syringe. What is the volume of gas in the syringe?

1. Identify the main numbered markings on the syringe scale (e.g., 80, 90). 2. Determine the value of the smaller markings between the numbers. The space between 80 and 90 is 10 cm³. There are 5 intervals, so each small line represents 10/5 = 2 cm³. 3. Locate the position of the plunger. It is on the third small line after 80. 4. Calculate the reading: 80 + (3 × 2) = 86 cm³.