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# 1.34 Concentration calculations

volumetric glassware is used to measure accurately volumes of solutions
the action or power of focusing all one's attention
Concentration Noun  :
1. the action or power of focusing all one's attention
2. a close gathering of people or things.
3. the relative amount of a particular substance contained within a solution or mixture or in a particular volume of space

In this topic we will of course be using the third definition of concentration

#### Students should:

• 1.34C understand how to carry out calculations involving amount of substance, volume and concentration

#### Activity 1. Moles, solutions and volumes

Watch the first 2 minutes and 45 seconds of the video. Use it to construct a formula triangle which connects Volume (V/dm3) (moles/dm3) and the number of moles n

A word of warning:  dm3 and cm3

A lot of reactions in the laboratory involve small volumes. It is often more convenient to work in cm3. This means we need to convert between dm3 and cm3 .

remember  1dm3 = 1000 cm3