Question

Two students Sam and Rohit were performing experiments in the science lab.

Sam mixed 10.6 g of sodium carbonate in a conical flask with 12 g of hydrochloric acid in an ignition tube. He took care that the solutions did not mix with each other. He then put a cork on the conical flask and weighed the flask with the ignition tube and its contents. After weighing the flask for the first time Sam tilted it and allowed the solutions to mix and react. He then weighed the conical flask again. Sam found that the mass of the flask with its contents both before and after the experiment was the same.

Rohit mixed 10.6 g of sodium carbonate in a conical flask with 12 g of Hydrochloric acid in ignition tube. He took care so that the solutions did not mix with each other. He weighed the flask with the ignition tube and its contents. He then tilted the conical flask to allow the solutions to mix and react. After the experiment, Rohit again weighed the conical flask. Rohit found that the mass of the flask with its contents both before and after the experiment was the not the same.

() State the law which was being tested in the experiment.

(ii)

Why did Rohit get a difference in the mass?​

Answer 1

Answer:

(i.) Law of conservation of mass.

Explanation: According to the law of conservation of mass, the mass of the products in a chemical reaction must be equal to the mass of the reactants.

(ii.) Rohit didn't put a cork on the the conical flask, due to which some of the contents in the flask may have fallen out of it on tilting. Therefore, the mass of the flask may have reduced from when it was observed the previous time.