Topic 5 Flashcards
What is the empirical formula?
The smallest whole number ratio of atoms of each element in a compound
What is the molecular formula?
Shows the actual numbers of the atoms of each element in a compound
What is the ideal gas equation
pV = nRT
What is a standard solution
A solution where the concentration is accurately known
What is an error
The difference between an experimental value and the accepted or correct value
- something even a skilled operator would find difficult to avoid
What is the difference between an error and mistake
A mistake is something that a skilled operator can avoid by being careful
An error would be difficult to avoid
Definition of accuracy
A measure of how close values are to the accepted or correct value
Definition of precision
Measure of how close values are to each other
What is a random error
Errors caused by unpredictable variations in conditions
What is a systematic error
Errors that are constant or predictable, usually because of the apparatus used
What is a measurement uncertainty
The potential error involved when using a piece of apparatus to make a measurement
Formula for percentage yield
(actual yield / theoretical yield) x100
Formula for atom economy
(molar mass of desired products / molar mass of all products) x100
How to calculate the number of molecules in a mass of a substance
- Find out the moles of the substance
- Times the amount of moles by Avogadro’s constant
What is meant by the term molar volume of a gas
Volume occupied by one mole of a gas at standard conditions
