Hi Ochaya,
The answer is A.
You were right that you need a balance to measure the grams of MgCO3 and a pipette to add HCI, but you don't need a thermometer-- after all we're measuring the /time/, so you need a clock.
Which pieces of apparatus does the student need?
A: Balance, clock, pipette
B: Balance, clock, thermometer
C: Balance, pipette, thermometer
D: Clock, pipette, thermometer
My answer is c so correct me if I am wrong.
The answer is A.
You were right that you need a balance to measure the grams of MgCO3 and a pipette to add HCI, but you don't need a thermometer-- after all we're measuring the /time/, so you need a clock.
Explanation:
To measure the time taken for a reaction to occur, the student will need a clock or timer. A pipette is used to accurately measure and transfer the volume of the hydrochloric acid. A thermometer is not necessary for this particular reaction. Lastly, a balance is not needed to measure the time, but it may be useful to measure the mass of the magnesium carbonate.