1. The following lesson is one lecture in a series of Chemistry Programs developed by Professor Larry Byrd Department of Chemistry Western Kentucky University

2. PART 3 Temperature Scales

3. EXAMPLE FIVE: Convert 12.6  C into  F. 1.  F = (1.8) (  C) + 32 Write the needed equation you had to learn 2.  F = (1.8) (12.6) + 32 Substitute the given value 3.  F = 22.68 + 32 Do math Round off 22.68 to the nearest tenth! 4.  F = 22.7 + 32 Do math 5.  F = 54.7 6. Thus, 12.6  C = 54.7  F

4. If we want to convert Fahrenheit readings into Celsius readings, we will need to rearrange the Fahrenheit (  F) equation: 1.  F = (1.8) (  C) + 32 Write the needed equation you had to learn 2. (1.8) (  C) + 32 =  F First, exchange sides 3. (1.8) (  C) + 32 - 32 =  F – 32 Next, subtract 32 from both sides 4. (1.8) (  C) + 32 - 32 =  F - 32 Do math 5. (1.8) (  C) =  F - 32

5. If we want to convert Fahrenheit readings into Celsius readings, we will need to rearrange the Fahrenheit (  F) equation: 6. Divide both sides by 1.8 7. Do math. Notice that the 1.8’s cancel 8.  C =

6.  C = In words, the above equation states that to convert a value given in Fahrenheit into a value in Celsius, we must do the following steps: 1. First subtract 32 from the Fahrenheit reading 2. Next, divide that value by 1.8 3. Then, round-off and give the new value with units of  C Study the following examples:

7. EXAMPLE SIX: The oral reading for a normal body temperature of a patient is 98.6  F. Convert that value into a Celsius reading. Notice, that we must round-off to the nearest tenth of a degree. 1.  C = Write needed equation 2.  C =Substitute the given value 3.  C = Do division and round-off to the nearest tenth 4.  C = 37.0 Give final answer to the nearest tenth, since 98.6  F was to the nearest tenth Thus, 98.6 °F is equal to 37.0 °C

8. EXAMPLE SEVEN: Convert -16.  F into  C: 1.  C = Write the needed equation 2.  C = Substitute the given value and Do algebraically 3.  C = Watch the negative sign! Divide ! 4.  C = - 26.6666666 This answer must be rounded off to the nearest whole number since the starting temperature, -16  F, was a whole number 5.  C = - 27.  C 6. Thus, - 16.  F is equal to -27.  C

9. EXAMPLE EIGHT: Convert 16.69  F into  C. [ Round-off to the nearest hundredth of a degree ] 1.  C = Write the needed equation 2.  C = Substitute the given value. 3.  C = Do math, watch signs and Do algebraically! 4.  C = - 8.505555 Round-off to the nearest hundredth 5.  C = - 8.51 6. Thus, 16.69  F is the equal to -8.51  C.

10. EXAMPLE NINE: Convert 75.6  F into K In doing this conversion, we must first convert  F into  C and then convert the Celsius(  C ) value into a Kelvin Value. (A) Convert 75.6  F into  C (Starting temperature is to the nearest tenth) 1.  C = Write the needed equation 2.  C = Substitute the given value and Do algebraically 3.  C = Do Math! 4.  C = 24.22222 Round-off to the nearest tenth 5.  C = 24.2 6. Thus, 75.6  F is equal to 24.2  C.

11. EXAMPLE NINE: Convert 75.6  F into K In doing this conversion, we must first convert  F into  C and then convert the Celsius(  C ) value into a Kelvin Value. (B) "NEXT" Convert 24.2  C into Kelvin: 1. K =  C + 273.2 Write the needed equation 2. K = 24.2 + 273.2 Substitute the given value 3. K = 297.4 Notice, that the answer was rounded- off to the nearest tenth Thus, 75.6  F is equal to 24.2  C and is also equal to 297.4 K