Dimensional Analysis Organized method of problem-solving Used in chemistry, physics, engineering, and medicine Communicates the path to scientists that follow your work Records your own path for your future use

Calculate the number of minutes in 3.61 hours. Dimensional Analysis Calculate the number of minutes in 3.61 hours. *Note: Use the number given in the question to determine the number of sig figs in your answer. 1. Write the given. 2. Draw the chart.

3. Think of a relationship: 1 hr = 60 min 5. Cancel units diagonally. Dimensional Analysis Calculate the number of minutes in 3.61 hours. *Note: Use the number given in the question to determine the number of sig figs in your answer. 3. Think of a relationship: 1 hr = 60 min 4. Divide the relationship in ½ at the = sign. 5. Cancel units diagonally.

6. Add the rest of the relationship. Dimensional Analysis Calculate the number of minutes in 3.61 hours. *Note: Use the number given in the question to determine the number of sig figs in your answer. 6. Add the rest of the relationship. Count sig figs in the given. Round the answer to that number of sig figs.

How many centimeters are in 4.2 inches? Dimensional Analysis How many centimeters are in 4.2 inches? *Note: Use the number given in the question to determine the number of sig figs in your answer.

How many centimeters are in 4.2 inches? Dimensional Analysis How many centimeters are in 4.2 inches? *Note: Use the number given in the question to determine the number of sig figs in your answer.

Realize that we don’t know just one step from weeks to seconds. Dimensional Analysis Multi-Step Problems Calculate the number of seconds in two weeks. Realize that we don’t know just one step from weeks to seconds.

Dimensional Analysis Multi-Step Problems Start as usual. Calculate the number of seconds in two weeks. Start as usual.

Dimensional Analysis Multi-Step Problems Extend your table. Calculate the number of seconds in two weeks. Extend your table.

Continue adding relationships. Dimensional Analysis Multi-Step Problems Calculate the number of seconds in two weeks. Continue adding relationships.

Add as many conversions as needed. Dimensional Analysis Multi-Step Problems Calculate the number of seconds in two weeks. Round to 1 sig fig. Add as many conversions as needed.

Notice the use of the bottom space. Dimensional Analysis Multi-Step Problems Convert the density of 0.58 g/mL to lb/gallon. (1 L = 1.057 qt and 4 qt = 1 gal; 1kg = 2.2 lb) Notice the use of the bottom space.

Ignore the bottom unit for a moment. Dimensional Analysis Multi-Step Problems Convert the density of 0.58 g/mL to lb/gallon. (1 L = 1.057 qt and 4 qt = 1 gal; 1kg = 2.2 lb) Ignore the bottom unit for a moment. Concentrate on converting the top unit.

Continue converting the top. Stop when you get to lb…the goal. Dimensional Analysis Multi-Step Problems Convert the density of 0.58 g/mL to lb/gallon. (1 L = 1.057 qt and 4 qt = 1 gal; 1kg = 2.2 lb) Continue converting the top. Stop when you get to lb…the goal.

Now, focus on the bottom units. Dimensional Analysis Multi-Step Problems Convert the density of 0.58 g/mL to lb/gallon. (1 L = 1.057 qt and 4 qt = 1 gal; 1kg = 2.2 lb) Now, focus on the bottom units. It is OK to cancel units from a distance.

Continue adding until you reach the goal. Dimensional Analysis Multi-Step Problems Convert the density of 0.58 g/mL to lb/gallon. (1 L = 1.057 qt and 4 qt = 1 gal; 1kg = 2.2 lb) Continue adding until you reach the goal.