In an experiment, rods of metals P, Q and R were cleaned with sand paper and placed in a beaker containing water. Another set of rods...

      

In an experiment, rods of metals P, Q and R were cleaned with sand paper and
placed in a beaker containing water. Another set of rods was also cleaned and
placed in a beaker containing dilute acid. After placing the rods in the two liquids
bubbles of gas were seen around some of the rods as shown in the diagrams
below.

a) Why is it necessary to clean the rods with sand paper before dipping them
into the liquids.
b) Arrange the three metals in order of their reactivity starting with the most
reactive.

  

Answers

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a) To remove oxide coating which could inhibit reaction
b) O R P

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Kavungya answered the question on June 22, 2019 at 04:26

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