Finding the rate law would be simple if we could observe the reactions at the

# Finding the rate law would be simple if we could

• 6

This preview shows page 3 - 6 out of 6 pages.

the rate law does not correspond to the balanced chemical equation. Finding the rate law would be simple if we could observe the reactions at the molecular level, but that is not possible. We must use indirect evidence. There are many experimental techniques that can be used to determine the rate law for a reaction. Determining the initial rate of a reaction and seeing how that initial rate changes when the concentrations of reactants are changed is one way of using experimental data to determine the rate law. Model 1 The Effect of Exponents y = kx n (where k = 5) 1. Consider the mathematical equation in Model 1 . a) What letter represents a constant in the equation? b) What is the value of the constant? c) What letter represents the exponent in the equation? d) Does x in the equation represent the independent variable , dependent variable or a constant ? Chemistry POGIL - Rates Ms. Park y = kx n (where k = 5) x if n = 0, then y = ? if n = 1, then y = ? if n = 2, then y = ? 1 2 3 y = 5· 3 0 = 5 4 2. Fill in the table in Model 1 using the mathematical equation provided. Divide the work with your partner. 3. Refer to Model 1 . Use complete sentences to describe the change in y as x increases when n = 0 . Justify the pattern you see using your knowledge of mathematics. 4. Refer to the column in the Model 1 table where n = 1 . a) When x doubles , what happens to y ? b) When x triples , what happens to y ? 5. Use a complete sentence to describe the change in y as x increases when n = 1 . Justify the pattern you see using your knowledge of mathematics. 6. Refer to the column in the Model 1 table where n = 2 . a) When x doubles , what happens to y ? b) When x quadruples , what happens to y ? 7. Use a complete sentence to describe the change in y as x increases when n = 2 . Justify the pattern you see using your knowledge of mathematics. 8. In conclusion, what is the effect of the exponent (n) ? 9. Consider the data below and determine the value of the exponent q . Justify your answer with an explanation or a mathematical equation. r = st q t r 5 15 10 30 15 45 10. Solve for the constant s in Question 8 above. Chemistry POGIL - Rates Ms. Park 11. Consider the data below and determine the value of the exponent q . Justify your answer with an explanation or a mathematical equation.  #### You've reached the end of your free preview.

Want to read all 6 pages?

• • •  