Chemical Change Flashcards
What does pH scale measure
How acidic or alkaline a solution is
What does it mean if a solution ahs a low or high pH
Lower pH of a solution is the more acidic it is
Higher pH of a solution the more acidic it is
What is neutral number on pH
7
How do strong acids ionise
They ionise completely in water.
How do week acids ionise
Do not fully ionise
What does pH of an alkali or acid measure the concentration of
It measures the concentration of H+ ions in the solution
How much does the concentration decease by if you go down pH scale by 1
For every decrease of 1 on the pH scale
For a decrease of 2 in the pH scale how much does the concentration of H+ ions decrease
100
Compare pH in a strong acid and a weak acid if they have the same concentration
Strong acid has lower pH than a week acid if they have the same concentration
What does the acid strength tell you
What proportion of the acid molecules ionise in water
What does concentration if an acid measure
Concentration measures how much acid there is in a certain volume of water
Can you have a dilute acid but its strong (y or n)
Yes
What is formed when metal oxides and hydroxides react with acids
Salt and water
What does metal carbinate form when it reacts with acid
Salt, water and carbon dioxide
How can you make a pure dry sample of a given solube salt (crystalisation)
Gently warn the dilute acud using a bunsen burner then turn iff the bunsen burner. Add the insolube base to the acid gradually until nonmore reacts. All acid is nutrialised if excess solid sinks to bottom. Then filter out excess solid to get salt solution. To get pure dolid crystals of salt use an electric heater to evaporate some of the water. Crystals of salt should be formed. This is called crystalisation.
