Take three test tubes. Fill 3//4th of each with water. Label them A,B and C. Keep a snail in test tubeA, a water plant in test-tube B and in C, keep snail and plant both. Which test-tube would have the highest concentration of`CO_2`?

Equal lengths of magnesium ribbons are taken in test tubes A and B. Hydrochloric acid (HCl) is added to test tube A, while acetic acid (CH_(3)COOH) is added to test tube B. Amount of concentration taken for both acids are same. In which test tube will the fizzing occur more vigorously and why ?

You have been provided with three test tubes. One of them cotains distilled water and the other two cotain an acidic solution and a basic solution, respectively. If you are given only red litmus paper , how will you identify the contents of each test tube ?

In the experimental set-up shown, a] Name the material X filled in the small test tube and the material Y placed at the bottom of the conical flask. b] Why is there a rise in water level in the delivery tube?

In test-tubes A and B , zinc sulphate solution and silver nitrate solution are taken respectively . Copper trunings are added to both test-tubes . In which of the two test-tubes do you observe the reaction. Justify your answer with scientific reason.

The elements Be, Mg, and 20Ca each having two valence electrons in their valence shells are in periods 2, 3, and 4 respectively of the Modern Periodic Table. Answer the following questions associated with these elements, giving reason in each case. a] In which group should they be? b] Which one of these is least reactive? c] Which one of them has the largest atomic size?