Acids, Bases & Salts + Periodic Table & Metals
What ion do acids produce?
H⁺ ions
What ion do alkalis produce?
OH⁻ ions
Define a base.
A substance that reacts with acids to form salt and water
Define an alkali.
A soluble base that produces OH⁻ ions in water
Define a salt.
A compound formed when H⁺ in an acid is replaced by a metal or ammonium ion
What is neutralisation?
Acid + base → salt + water
Acid + metal → ?
Salt + hydrogen
Test for hydrogen gas?
Pops with a lit splint
Acid + base → ?
Salt + water
Acid + carbonate → ?
Salt + water + carbon dioxide
Test for carbon dioxide gas?
Turns limewater milky
How do you make an insoluble salt?
Mix two soluble solutions, filter, wash, dry the precipitate
Which salts are always soluble?
All nitrates
Which chlorides are insoluble?
Silver chloride and lead(II) chloride
Which sulfates are insoluble?
Barium sulfate and lead(II) sulfate
Most carbonates are…?
Insoluble (except sodium, potassium, ammonium)
Most hydroxides are…?
Insoluble (except sodium, potassium, ammonium)
What happens to reactivity down Group 1?
It increases
What happens to melting point down Group 1?
It decreases
Group 1 metals + water → ?
Metal hydroxide + hydrogen
What happens to reactivity down Group 7?
It decreases
What is a halogen displacement reaction?
A more reactive halogen displaces a less reactive halogen from a compound
Why are noble gases unreactive?
They have a full outer electron shell
Why does atomic size decrease across a period?
Increasing nuclear charge pulls electrons closer
Metals form what type of ions?
Positive ions (cations)
Non-metals form what type of ions?
Negative ions (anions)
Describe metallic bonding.
Positive metal ions in a sea of delocalised electrons
Why are metals good conductors?
Delocalised electrons move freely
Which metals are extracted by electrolysis?
Metals more reactive than carbon (e.g. aluminium)
Which metals are extracted by reduction with carbon?
Metals less reactive than carbon (e.g. iron)
What are native metals?
Unreactive metals found uncombined (e.g. gold)
Name the products when sodium reacts with water.
Sodium hydroxide and hydrogen
Why does potassium react more strongly than lithium?
Outer electron is further from nucleus and more easily lost