Lesson 2.2 - Blending Water

You will not perform this activity, but you will be asked to predict what will happen if you did perform it. 

Read the Find Out Activity on page 87 of your textbook, and answer the following questions.  

Question 1. Do the two beakers of water (100 mL each) have the same temperature?

Question 2. When the hot and cold water are mixed together, would the water have the same temperature?

A student performed the activity and obtained the following observations:

Water

Temperature

100 mL hot

70°C

100 mL cold

10°C

200 mL mixture

 

Question 3. What do you predict the temperature of the mixture to be?

Check your answers with those that follow.

 

 

 

 

 

 

 

 

 

 

 

Answers to Questions:

Question 1. Do the two beakers of water (100 mL each) have the same temperature?

No. One had hot water; the other had cold water.  The temperatures were different.

Question 2. When the hot and cold water are mixed together, would the water then have the same temperature?

The mixed water would have the same temperature.  You could not have some parts of the water cold and some parts hot; they are mixed together.  Note that the "same temperature" does not mean hot or cold; it would be warm.

Question 3. What do you predict the temperature of the mixture to be?

Because the volume of both hot and cold water was the same, the temperature of the mixture should be the average temperature.

(70°C + 10°C)/2 = 40°C 


Go to the next page to continue learning about heat and temperature.