Chem Rate of Rxn Ws3

Secondary 4 Express Pure Chemistry – Rate of Reaction Worksheet 3 SDL Page 1 of 8 Name: _____________________( ) Class: _______ Date ________ 1. The graph shows the total volume of carbon dioxide evolved, plotted against time, when excess calcium carbonate reacts with 20 cm3 of hydrochloric acid containing 2moldm-3. (a) Give a balanced chemical equation for the reaction above. __________________________________________________________________ (b) Indicate clearly on the graph above the time taken for the reaction to end (TE) (c) Indicate clearly on the graph how the rate of the reaction can be obtained at pt X (d) Read the facts provided and answer the following questions. (i) What is the name of the product measured? ______________________________ (ii) How is the product in (di) collected and measured for the rate of reaction? _________________________________________________________________ (iii) What are the reactants present? _______________ and ____________________ (iv) Which reactant will be used up first? Explain. _________________________________________________________________ (e) If the experiment was repeated but this time the concentration of the acid was changed to 0.5mol/dm3, sketch on the graph above what you would expect and label the graph as Rxn II (f) Explain in terms of the collision theory how concentration has affected the rate of reaction.

Secondary 4 Express Pure Chemistry – Rate of Reaction Worksheet 3 SDL Page 2 of 8 _________________________________________________________________ _________________________________________________________________ _________________________________________________________________ 2. Two experiments are carried out using the apparatus below. In experiment 1, dilute acid is used In experiment 2, more concentrated hydrochloric acid is used. All other conditions are the same and in both experiments all the marble chips completely react. (a) What is the chemical formula of marble chip? _________________________ (b) What is the observation when marble chip allowed to react with hydrochloric acid? ______________________________________________________________ ______________________________________________________________ (c) Give a balanced chemical equation of the above reaction. ______________________________________________________________ (d) State the difference in terms of ions between the two acids in experiment 1 and 2. ______________________________________________________________ (e) Which diagram shows the correct results obtained for the above experiments?

Secondary 4 Express Pure Chemistry – Rate of Reaction Worksheet 3 SDL Page 3 of 8 Explain your answer in (e) _________________________________________________________________ _________________________________________________________________ 3. Curve 2 shows the volume of carbon dioxide given off wh