Acids and Bases Flashcards
What is an acid
A proton donor
HCl->
H+ + Cl-
Name the three common acids
Hydrochloric acid (HCl)
Sulfuric acid (H2SO4)
Nitric acid (HNO3)
What makes an acid strong
It can fully ionise- disassociate (gives away H+)
Name two strong acids
Hydrochloric acid
Sulfuric acid
What makes an acid weak
It partially ionises
Give an example of a weak acid
Ethanoic acid (CH3COOH)
CH3COOH <=>
H+ + CH3COO-
What determines an acids concentration
The amount of H+ ions
What is an alkali
A proton acceptor
Describe an alkali
A base dissolved in water
Give an example of a strong alkali
Sodium hydroxide (NaOH)
Give an example of a weak alkali
Ammonia (NH3)
What is the PH of acids
0-6
What is the PH of alkali’
8-14
What is a salt
What’s formed when a metal replaces the hydrogen of an acid
How do you convert from Moldm-3 to gdm-3
Multiply by the Mr
What is volumetric analysis
A chemical procedure used for determining the concentration of a solution
What is the equivalent point
The point where the exact amount of acid has reacted with the alkali according to the equation
What are the requirements for titrations (4)
- fast reaction
- reaction must go to completion (large equilibrium constant)
- free from any side reactions (represented by a single equation)
- must be able to determine through observation and the equivalence point
Name two universal indicators
Methyl-orange, phenolphthalein
Describe methyl-orange indicator
Changes from red-yellow at PH3.1 (acid-alkali)
Describe phenolphthalein
Turns from colourless to pink at PH8 (acid-alkali)
What dp do you always write titrations to unless stated otherwise
2 decimal places
Define accurate
Getting a correct value
Define precise
How close repeat values are to each other
How to calculate percentage uncertainty
Uncertainty (x however many times you used the object)/measurement
((X100))
How do you minimise percentage uncertainty in titrations
Use a pipette/burette (very accurate)
