A piece of marble chip ( calcium carbonate) is put in a beaker containing excess of dilute hydrochloric acid which is placed on a reading balance....

A piece of marble chip ( calcium carbonate) is put in a beaker containing excess of dilute hydrochloric
acid which is placed on a reading balance. The mass of the beaker and its contents is recorded every
two minutes, as shown in the table.

(a) Why is there a continuous loss of mass of the reaction mixture.
(b) Write an equation for the reaction taking place.
(c ) State two different ways by which the reaction could have been made more rapid.
(d) Why does the mass remain constant after 8 minutes.
(e) State the observations that would be made if a few drops of silver nitrate solution
Was added to 1cm³ of the resulting solution followed by ammonia solution.

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(a) Carbon (IV) oxide formed is escaping.

(c ) - Increasing the temperature
- Increasing the concentration of hydrochloric acid
- Using powdered calcium carbonate instead of marble chips
(d) All the marble chips have been used up // the reaction has come to an end.
(e) White precipitate formed which dissolves in ammonia solution

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sharon kalunda answered the question on May 17, 2019 at 10:16

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