Question

multiple choice question
which of the following represents an experiment that is performed with multiple trials?

the temperature of a container of baking soda is measured three times after 30 ml of vinegar is added.
the temperature of three containers of baking soda is measured just after 30 ml of vinegar is added to them.
the temperature of a container of baking soda is measured before baking soda is added to the container, just after baking soda is added to the container and after 30 ml of vinegar is added to the container.
the temperature of a container of baking soda, salt and calcium carbonate is measured just after 30 ml of vinegar is added to it.

Explanation:

Multiple - trials experiments involve repeating the same experimental procedure multiple times. In the first option, measuring the temperature of a container of baking soda three times after adding vinegar is a repetition of the same measurement process on the same sample. The second option measures different containers (not multiple trials on the same setup). The third option measures at different stages of adding substances rather than repeating the same trial. The fourth option is a single - measurement on a combined mixture.

Answer:

The temperature of a container of baking soda is measured three times after 30 ml of vinegar is added.