1.1. A student investigated the effect of temperature on the rate of reaction.

Figure 1 shows the equipment they used.

Figure 1

The student added dilute hydrochloric acid to the sodium thiosulfate solution. A cloudy solution was produced. The student timed how long it took for the cross to disappear. This was repeated at different temperatures.

Complete the balanced symbol equation for the reaction.

Na₂S₂O₃ (aq) + ___ HCl (aq) → ___ NaCl (aq) + H₂O (l) + SO₂ (g) + S (s)

1.2. The reaction mixture turned cloudy.

What is produced in the reaction that caused the mixture to turn cloudy?

Use the equation in part (a).

1.3. At 30 ^oC, 0.46 g of sulfur was produced in 58 seconds.

Use the equation below to calculate the mean rate for reaction at 30 ^oC.

            $Meanrateofreaction=\frac{massofsulfurproduced}{timetaken}$

Give your answer to 2 significant figures.

Mean rate of reaction: ____________________ g / s 

1.4. The student found that as the temperature of hydrochloric acid increased, the time taken for the cross to disappear decreased.

Complete the sentences using words from the box below.

The rate of reaction ____________________ as the temperature increases.

This is because the particles are moving ____________________ and the particles collide with ____________________  energy.