Changes

[[Molarity]] is the a[[unit]]s of [[concentration]] of a [[solution]]s.

: [[Molarity]] is shortened with an upper case '''M'''.: When [[molarity]] is used to describe a [[solution]] it may be referred to as '''molar''', eg A . a 0.5 '''molar''' [[solution]] of [[Sodium Chloride]].

: The [[molarity]] of [[Stomach Acid]] is around 0.16 '''Molar''' (0.16M).: The [[molarity]] of [[Battery Acid]] can be as much as 5.2 '''Molar''' (5.2M). ==Key Stage 4=====Meaning===[[Molarity]] is a [[unit]] of [[concentration]] of [[solution]]s in mol/dm³. ===About Molarity===: [[Molarity]] is shortened with an upper case '''M'''.: [[Molarity]] is the [[ratio]] of the number of [[mole]]s of a [[solute]] to the [[Volume (Space)|volume]] of [[solvent]].: When [[molarity]] is used to describe a [[solution]] it may be referred to as '''molar''', eg. a 0.5 '''molar''' [[solution]] of [[Sodium Chloride]].: Bottles containing [[acid]] and [[alkali]] usually have their [[Molarity]] stated on the side. The more [[concentrated]] the higher the [[molarity]]. ===Equation==='' '''concentration (mol/dm³)''' '' = <math>\frac{Moles (mol)}{volume (dm^3)}</math> Where:: Moles = The number of [[mole]]s of the [[solute]]. Found by dividing the [[mass]] in [[gram]]s by the [[Relative Formula Mass|relative formula mass]].: volume = The [[Volume (Space)|volume]] of [[solvent]]. ===Calculating Molarity==={| class="wikitable"|-| style="height:20px; width:300px; text-align:center;" |117g of [[NaCl]] is [[dissolve]]d in 0.5dm³ of [[water]]. Calculate the [[concentration]] in g/dm³.| style="height:20px; width:300px; text-align:center;" |28g of [[KOH]] is [[dissolve]]d in 100ml of [[water]]. Calculate the [[concentration]] in g/dm³.| style="height:20px; width:300px; text-align:center;" |7.3g of [[HCl]] is [[dissolve]]d in 400ml of [[water]]. Calculate the [[concentration]] in g/dm³.|-| style="height:20px; width:200px; text-align:left;" |'''Find the number of [[mole]]s.'''[[mass]] = 117g [[Relative Formula Mass]] = 58.5g Number of [[Mole]]s of a [[Compound]] = ([[Mass]] of [[compound]])/([[Relative Formula Mass]] of [[compound]]) Number of [[Mole]]s = <math>{\frac{m}{M_r}}</math> Number of [[Mole]]s = <math>{\frac{117}{58.5}}</math> Number of [[Mole]]s = 2mol  | style="height:20px; width:200px; text-align:left;" |'''State the [[mass]] in [[gram]]s and the [[Volume (Space)|volume]] in dm³:''''''Find the number of [[mole]]s.'''[[mass]] = 28g [[Relative Formula Mass]] = 56g Number of [[Mole]]s of a [[Compound]] = ([[Mass]] of [[compound]])/([[Relative Formula Mass]] of [[compound]]) Number of [[Mole]]s = <math>{\frac{m}{M_r}}</math> Number of [[Mole]]s = <math>{\frac{28}{56}}</math> Number of [[Mole]]s = 0.5mol| style="height:20px; width:200px; text-align:left;" |'''Find the number of [[mole]]s.'''[[mass]] = 7.3g [[Relative Formula Mass]] = 36.5g Number of [[Mole]]s of a [[Compound]] = ([[Mass]] of [[compound]])/([[Relative Formula Mass]] of [[compound]]) Number of [[Mole]]s = <math>{\frac{m}{M_r}}</math> Number of [[Mole]]s = <math>{\frac{7.3}{36.5}}</math> Number of [[Mole]]s = 0.2mol|-| style="height:20px; width:300px; text-align:left;" |[[Volume (Space)|volume]] = 0.5dm³| style="height:20px; width:300px; text-align:left;" |[[Volume (Space)|volume]] = 100ml The [[Volume (Space)|volume]] must be converted into dm³ from ml. [[Volume (Space)|volume]] in dm³ = ([[Volume (Space)|volume]] in ml)/1000 [[Volume (Space)|volume]] = 0.1dm³| style="height:20px; width:300px; text-align:left;" |[[Volume (Space)|volume]] = 400ml The [[Volume (Space)|volume]] must be converted into dm³ from ml. [[Volume (Space)|volume]] in dm³ = ([[Volume (Space)|volume]] in ml)/1000 [[Volume (Space)|volume]] = 0.4dm³ |-| style="height:20px; width:300px; text-align:left;" |'''Calculate the Concentration:''' '' '''concentration (mol/dm³)''' '' = <math>\frac{Moles (mol)}{volume (dm^3)}</math> '' '''concentration''' '' = <math>\frac{2}{0.5}</math> '' '''concentration''' '' = 4mol/dm³ = 4M| style="height:20px; width:300px; text-align:left;" |'''Calculate the Concentration:''' '' '''concentration (mol/dm³)''' '' = <math>\frac{Moles (mol)}{volume (dm^3)}</math> '' '''concentration''' '' = <math>\frac{0.5}{0.1}</math> '' '''concentration''' '' = 5mol/dm³ = 5M| style="height:20px; width:300px; text-align:left;" |'''Calculate the Concentration:''' '' '''concentration (mol/dm³)''' '' = <math>\frac{mass (g)}{volume (dm^3)}</math> '' '''concentration''' '' = <math>\frac{0.2}{0.4}</math> '' '''concentration''' '' = 0.5mol/dm³ = 5M|}