Measuring volume of gas by displacement

The image below shows a set-up for collecting the gas produced during the reaction between calcium carbonate and hydrochloric acid.

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In order to measure the rate of reaction the upturned test tube would need to be replaced with a measuring cylinder. 

Students would be expected to assemble this apparatus themselves and in addition they would need to record data against time in order to determine the rate. For many students this can be very challenging.

Suggest what parts of this activity might provide the greatest challenge.

Placing the delivery tube in the correct location.

Securing the measuring cylinder.

Placing the bung into the conical flask.

Starting the stop clock at the same time as the reaction begins.

Accurately measuring the volume of gas produced.

Inverting the water-filled measuring cylinder under water.

Measuring volume of gas by displacement

The image below shows a set-up for collecting the gas produced during the reaction between calcium carbonate and hydrochloric acid but in this case the gas volume is measured using a gas syringe.

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By using this method which of the following difficulties (highlighted previously) is removed?

Placing the delivery tube in the correct location.

Securing the measuring cylinder.

Placing the bung into the conical flask.

Inverting the water-filled measuring cylinder under water.

Note that an inexpensive gas syringe can be made by lubricating the plunger of a plastic syringe with silicone gun oil (CLEAPPS method needs to be looked up).