A few drops of sap were collected by cutting across a plant stem by a suitable method. The sap was tested chemically. Which one of the following test results indicates that it is phloem sap ?

Which one of the following indicates that a diagnostic test is valid?

Which one of the following features is an indication for modification of stem of a plant?

A flame test was performed to confirm the identity of a metal ion in solution. The result was a green flame. Which of the following metal ions is indicated?

A student took solution X in a test -tube and added a few drops of universal indicator to it. The solution turned blue. On addind another solution Y to this test tube drop wise, the colour of solution changed to green. When a yet another solution Z was added the solution turned yellow. Which of the following gives the correct conclusion of the student?

Few simple chemical tests are given below to differentiate between the pairs of compounds.Which of the following tests is not correct for differentiation ?

A student was asked to test an unknown colourless solution with an indicator. When he added a few drops of phenolphthalein indicator, the solution turned pink. Which one of the following chemicals should be added in excess so as to obtain the colourless solution again?