Measuring rates of reaction
The rate of reaction A measure of how the speed of a chemical changes over the course of the reaction. It may be determined by measuring the loss of a reactant or gain of a product over time. can be found by measuring the amount of productsSubstances formed in a chemical reaction. formed, or the amount of product lost, over a certain period of time.
The massThe amount of matter an object contains. Mass is measured in grams (g).of a solid product is measured in grams, while the volumeThe volume of a three-dimensional shape is a measure of the amount of space or capacity it occupies, eg an average can of fizzy drink has a volume of 330 cm3. of a gaseous product is measured in cm3.
Rate is most often calculated using the equation: rate = \( \frac {1}{time}\) where the time is the time for the reaction to reach a certain point or the time for the reaction to be completed. The units of rate calculated in this way are s-1.
Measuring the rate when a gas is produced
The apparatus you use depends on the nature of the product being measured.
- the mass of a substance - solid, liquid or gas - is measured with a balance.
- the volume of a gas is usually measured with a gas syringe (or sometimes with an upside-down measuring cylinder).