English | Español

Try our Free Online Math Solver!

Online Math Solver












Please use this form if you would like
to have this math solver on your website,
free of charge.

Temperature and Density

Reading: Ch. 2 sections 7 - 8 Homework:
2.7, questions 72, 74, 76, 78*, 82*
2.8, questions 86, 90, 92*, 94*, 96, 100*

* = ‘important’ homework question


Background: There are three temperature scales in common use today . Can
you name them?

How were the end points of the two ‘metric’ scales defined? In other words,
what natural conditions define these respective temperature values ?

The Centigrade and Kelvin
The Centigrade scale compared to the
of H2O

Converting between Degrees Celsius and Kelvin

Task: By looking at the above graph , describe how the °C and K scales are
related. What do they have in common ? What is different ?

Simply add 273.15 to ANY temp. quoted in °C to obtain
the equivalent K value


Simply subtract 273.15 from ANY temp. quoted in K to
obtain the equivalent °C value


1. What is 50°C in Kelvin?

2. What is 200 K in Celsius?

Comparing the Fahrenheit , Kelvin and Celsius Temperature Scales

Discussion: We saw that the end points for the °C scale corresponded to
specific ‘natural’ temperatures – the same is true for the °F scale. What
‘natural’ temperatures do you think 0 °F and 100 °F correspond to in
nature. How about 212 °F and 32 °F?

“You want to put
what, where?!..”

Diagram: Fahrenheit, Celsius and Kelvin thermometers side by side.

Question: What is the obvious error in the above diagram?

Task: By looking at the previous diagram , or the slide provided, describe
how the °C and °F scales are related. What do they have in common? What
is different ?

The two basic differences between the °C and °F scales
allow for equations relating them (conversion equations)
to be constructed:

For converting °C to °F:

For converting °F to °C:

Question: What is 90 °F in °C and in Kelvin?

Ask me about the extra credit temperature….

Temperature Ranges

Discussion: If something is boiling, is it necessarily ‘hot’?
If it is frozen, is it necessarily ‘cold’?

Task: View and make brief notes on the ‘temperature scale’ slide. Think of
the ‘hottest’ and ‘coldest’ things you come into contact with on a daily basis
– where do they fit into the ‘bigger picture’?



Review: How was the property of density defined during a previous lecture?


Where: ‘amount of matter’ = _______________

Discussion: What is the S.I. unit of density? Is this a convenient unit?

=> Density =

Question: What are the two ‘convenient’ derived S.I. units of density used
by chemists?

Prev Next