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A form 4 student carried out an experiment with 40 cubic centimeters of 1.0M hydrochloric acid and Marble...

Rates and reactions:
A form 4 student carried out an experiment with 40 cubic centimeters of 1.0M hydrochloric acid and Marble chips in order to determine rates of reaction using the following steps.
??HCL was poured to a conical flask
??Conical flask was then placed on a weighing balance
??20 grams of marble chips was then added to acid and left for reaction to proceed
??With time, Changes in mass of flask with contents was recorded
(a) State other way in which one can measure rate of reacion(1mk)
(b)(i) Sketch curve that will be obtain if mass of contents in flask is plotted against time label it as (k) (2mks)
(ii) Using the same axes sketch curve that will be obtain if powdered marble had been used(1mk)
(c) Write a chemical equation to show how reaction proceed (1mk)

Answers

Yegon
Answers:
(a) One can measure the volume of gas(carbon(iv) oxide produce against time by connecting a freely moveable syringe??
(b) (I) A curve has
??Axes (y)mass of marble chips in grams and (x) time in minutes(1mk) 1/2 for y and 1/2 for x
??Curve shape is slanting it shows that as the time proceed the mass of contents
decrease(inversely proportional) and it flattens at a point
(II)The curve slants above the (k) curve and flattens at the same point.
(c) CaCO3(s) +HCL(aq)-CaCl2(aq)+CO2(g)+H2O(l)
Kipssben answered the question on August 13, 2018 at 09:19

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