Chemical Changes Flashcards
Master the Chemical Changes topic
What is the mnemonic for oxidation and reduction?
OILRIG
What compounds are formed when metals react with oxygen?
Metal oxides
Which kinds of ions do metals form?
Positive ions, as they lose electrons
Recite the reactivity series.
Potassium Sodium Lithium Calcium Magnesium Zinc Iron Copper
Which substances does potassium react with?
Oxygen (burns), water, and acids (violently)
Which substances does sodium react with?
Oxygen (burns), water, and acids (violently)
Which substances does lithium react with?
Oxygen (burns), water, and acids (violently)
Which substances does calcium react with?
Oxygen (burns), water and acids
Which substances does magnesium react with?
Oxygen (burns), water and acids
Which substances does zinc react with?
Oxygen (forms oxide when heated), acid
Which substances does iron react with?
Oxygen (forms oxide when heated, acid (slowly)
Which substances does copper react with?
Oxygen (forms oxide when heated)
Which metals can be extracted using carbon?
Any that are lower in the reactivity series
Where is carbon in the reactivity series?
Between Magnesium and Zinc
What is extraction using carbon called?
Reduction with carbon
What are the four ways salts can be made?
acid + metal oxide → salt + water
acid + metal hydroxide → salt + water
acid + metal → salt + hydrogen
acid + metal carbonate → salt + water + carbon dioxide
What is the chemical formula for hydrochloric acid?
HCl
What is the chemical formula for nitric acid?
HNO3
What is the chemical formula for sulfuric acid?
H2SO4
Which ions do acids produce in aqueous solutions?
Hydrogen ions (H+)
In neutralisation reactions, which ions react with what to produce what?
Hydrogen ions react with hydroxide ions to produce water
H+(aq) + OH-(aq) → H2O(l)
Is a pH of 14 acidic or alkaline?
Alkaline.
What are the steps of a titration?
eg:
- Use a pipette to transfer 25cm^3 of sodium hydroxide solution into a conical flask
- Add 5 drops of indicator such as methyl orange to the flask
- Fill a burette with sulfuric acid
- Add acid to the alkali until the solution is neutral. Once you start to see a colour change, only add acid drop by drop. Swirl as you go along to make sure they mix
- Read the volume of acid added from the burette
- Repeat until you have two results within 0.1cm^3
How do you do titration calculation?
- Convert volumes to dm^3
- Determine the number of moles of the reactant where you know the concentration
- Work out the mole ratio
- Calculate the concentration.