Chemistry Topic 1

Define Avagadro’s constant

The nuber of atoms of carbon in 12.00g of C-12.

Relative molecular mass units

none

Molar mass units

gmol^-1

Define the Empirical Formula

the simplest whole number ratio of the elements in a compound

Define the Molecular Formula

a whole-number multiple of the empirical formula of a compound

What happens to the number of moles and concentration when something is diluted

Number of moles stays the same, volume is increased, concentration decreases

Define concentration

a measure of the amount of solute ina specified volume of a solvent

Define limiting reagent

The reactant that determines the amount of product that can be formed (other reactants are said to be in __**excess**__)

Calculate percentage yield

(actual/theoretical) x 100 %

Define Standard Solution

A solution with an accurately known concentration

Define Primary Standard

Substances that are so pure that the no. of mol can be accurately calculated from their mass

Define the equivalence point

The point in titration when the chemicals mixed have reacted in the mole ratio indicated by the balanced chemical equation

Define solution

a homogenous mixture of a solute and a solvent

Diagram of homogenous and heterogenous solution

**Heterogeneous solutions are those that have non-uniform compositions and properties throughout the solution.** 

\
Homogeneous solutions are those that have the same composition and properties throughout the solution. 

Boyle’s Law

Pressure is inversely proportional to Volume at a constant temperature

Charle’s Law

Volume is proportional to temperature at a constant pressure

Gay Lussac’s Law

Pressure is proportional to temperature at a constant volume

When is a gas ideal

* particles are completely independent
* volume of individual gas particles is negligible
* PV/RT = 1

Avogadro’s Law

Equal volumes of gases at the same temperature and pressure contain equal numbers of particles. (Volume is proportional to no. of mol)

Molar volume at STP

22\.7dm^3

dm^3 with

kPa

m^3 with

Pa

When do real gases behave the most ideal

High Temperature, Low pressure