EXPERIMENT: AFFECT OF SOLUTION CONCENTRATION ON REACTION RATE

Do this experiment. WEAR GOGGLES

These supplies are needed:

•chalk crumbs or dust
•0.1 M HCl - see previous experiment
•clean test tubes (5)
•metric balance
•weighing paper
Follow these directions.

Use the following investigation to check a general rule for the rate of reaction. Before beginning, write a hypothesis stating what effect increasing the concentration of one of the reactants should have on the rate of the reaction. Design an investigation to be able to get timed data for this system. Start the timing assoon as the chalk is mixed with the appropriately diluted acid solution. Set up each reaction solution (as designated in the table below) in a separate test tube. Carefully weigh out 5 , 0.1 g samples of crushed chalk on weighing paper. Pour one sample into the 0.05 M test-tube. Time the reaction. The reaction has finished when all outward signs of reaction have stopped. (This should be obvious for this reaction.) Repeat these steps for the remaining samples and record the appropriate times.Experimental data.

Solution Chalk 0.1 M HCl Water Final Concentration Time (sec.)
A 0.1g 5 mL 5 mL 0.05 M
B 0.1g 4 mL 6 mL
C 0.1g 3 mL 7 mL
D 0.1g 2 mL 8 mL
E 0.1g 1 mL 9 mL

Plot this data as final concentration of HCl solution vs. time.

Analyze your results.

a. Calculate the solution concentration for each of the HCl samples. The first one has been done for you.

b. As the concentration of the HCl solution increased, did the speed of the reaction increase or decrease?

c. Therefore, as the concentration of a reactant increases, does the rate of the reaction increase or decrease?

d. Do your predictions previous to this investigation agree with your results?

e. Make a general rule about the effects of concentration of reactants on reaction rates.

On the basis of your ideas about the number of collisions compared to concentration, justify your general rule for concentration of reactants versus reaction rates.

Question

EXPERIMENT: AFFECT OF SOLUTION CONCENTRATION ON REACTION RATE

Do this experiment. WEAR GOGGLES

These supplies are needed:

•chalk crumbs or dust
•0.1 M HCl - see previous experiment
•clean test tubes (5)
•metric balance
•weighing paper
Follow these directions.

Use the following investigation to check a general rule for the rate of reaction. Before beginning, write a hypothesis stating what effect increasing the concentration of one of the reactants should have on the rate of the reaction. Design an investigation to be able to get timed data for this system. Start the timing assoon as the chalk is mixed with the appropriately diluted acid solution. Set up each reaction solution (as designated in the table below) in a separate test tube. Carefully weigh out 5 , 0.1 g samples of crushed chalk on weighing paper. Pour one sample into the 0.05 M test-tube. Time the reaction. The reaction has finished when all outward signs of reaction have stopped. (This should be obvious for this reaction.) Repeat these steps for the remaining samples and record the appropriate times.Experimental data.

Solution	Chalk	0.1 M HCl	      Water	   Final Concentration	Time (sec.)
A	          0.1g	5 mL         	5 mL	   0.05 M	
B	         0.1g  	4 mL          	6 mL		
C	        0.1g	        3 mL	               7 mL		
D	        0.1g	        2 mL	               8 mL		
E	        0.1g	       1 mL	               9 mL

Plot this data as final concentration of HCl solution vs. time.

Analyze your results.

a. Calculate the solution concentration for each of the HCl samples. The first one has been done for you.

b. As the concentration of the HCl solution increased, did the speed of the reaction increase or decrease?

c. Therefore, as the concentration of a reactant increases, does the rate of the reaction increase or decrease?

d. Do your predictions previous to this investigation agree with your results?

e. Make a general rule about the effects of concentration of reactants on reaction rates.

On the basis of your ideas about the number of collisions compared to concentration, justify your general rule for concentration of reactants versus reaction rates.

jfraser · Answer

sounds like an interesting lab, that should get you some definitive results. You should try it!