Chemical Calculations and Organic Chemistry

Vocabulary flashcards covering definitions and key concepts in A-level chemistry, focusing on chemical calculations, organic chemistry (alkanes, alkenes, alcohols, carbonyls, carboxylic acids) and titrations.

Mole

The amount of substance in grams that has the same number of particles as there are atoms in 12 grams of carbon-12. Moles = \frac{Mass}{Mr}

Relative atomic mass

The average mass of one atom compared to one twelfth of the mass of one atom of carbon-12

Molar Mass

The mass in grams of 1 mole of a substance and is given the unit of g mol-1

Hydrated salt

A salt containing water molecules combined in a definite ratio as an integral part of the crystal

Anhydrous salt

A salt that contains no water of crystallization

Avogadro's Constant

There are 6.02 x 1023 atoms in 12 grams of carbon-12. Also, 'One mole of any specified entity contains 6.02 x 1023 of that entity' Constant = 6.02 x 10^{23} mol^{-1}

Parts per million (ppm)

The mass of substance in mixture divided by the total mass of mixture all multiplied by 1000 000 ppm = \frac{mass \ of \ substance}{total \ mass} x \ 10^6

Molecular formula

The actual number of atoms of each element in the compound

Empirical formula

The simplest ratio of atoms of each element in the compound

Solution

A mixture formed when a solute dissolves in a solvent

Enthalpy change of neutralisation

The enthalpy change when solutions of an acid and an alkali react together under standard conditions to produce 1 mole of water

Enthalpy change of atomisation

The enthalpy change when a mole of gaseous atoms is formed from an element in its standard state

Enthalpy change

The amount of heat