2. Inorganic Chemistry Flashcards
(26 cards)
How do alkali metals react with water?
They produce hydroxides and hydrogen gas, becoming more reactive down the group.
How do reactions with air/water show trends in alkali metals?
Reactivity increases down the group.
What are the physical states and colours of chlorine, bromine, iodine?
- Cl₂: green gas
- Br₂: red-brown liquid
- I₂: grey solid/violet vapour
How does reactivity change in Group 7 (Halogens)?
Reactivity decreases down the group.
What are the main gases in dry air?
- Nitrogen (78%)
- Oxygen (21%)
- Argon (0.9%)
- Carbon dioxide (0.04%)
How to determine oxygen percentage?
By observing reactions of metals or non-metals with air.
What are the products of combustion?
- Metals: metal oxides
- Hydrocarbons: CO₂ and H₂O
- Sulfur: SO₂
How are metals arranged in the reactivity series?
Based on their reactivity with water and acids.
What is rusting and how to prevent it?
Iron reacts with oxygen and water; prevented by barrier methods, galvanizing, or sacrificial protection.
What is oxidation and reduction?
- Oxidation: loss of electrons
- Reduction: gain of electrons
How to identify acids and alkalis with indicators?
- Litmus turns red in acid, blue in alkali
- Phenolphthalein turns pink in alkali
- Methyl orange: red in acid, yellow in alkali.
What does pH measure?
Acidity or alkalinity; 0–3 (strong acid), 4–6 (weak acid), 7 (neutral), 8–10 (weak alkali), 11–14 (strong alkali).
How do acids and alkalis neutralize?
Acids donate H⁺ ions; alkalis donate OH⁻ ions, forming water and salts.
What are rules for solubility?
- Sodium, potassium, ammonium salts are soluble
- Nitrates are soluble
- Silver and lead chlorides are insoluble
- Barium, calcium, lead sulfates are insoluble
- Carbonates insoluble except for Na, K, NH₄
- Hydroxides insoluble except for Na, K, Ca.
How are salts prepared?
By reacting acids with metals, metal oxides, hydroxides, or carbonates; filter, wash, and dry.
How to test for hydrogen?
Place a burning splint; squeaky pop.
How to test for oxygen?
Relights a glowing splint.
How to test for carbon dioxide?
Bubble through limewater; turns cloudy.
How to test for ammonia?
Turns damp red litmus paper blue.
How to test for chlorine?
Turns damp litmus paper white (bleaches).
What are the flame test colours for Li⁺, Na⁺, K⁺, Ca²⁺, Cu²⁺?
- Li⁺: red
- Na⁺: yellow
- K⁺: lilac
- Ca²⁺: orange-red
- Cu²⁺: blue-green.
How to identify metal cations with NaOH?
Form characteristic precipitates: Cu(OH)₂ (blue), Fe(OH)₂ (green), Fe(OH)₃ (brown).
How to identify halide ions?
Acidified AgNO₃: Cl⁻ (white precipitate), Br⁻ (cream), I⁻ (yellow).
How to test for sulfate ions?
Acidified BaCl₂: forms a white precipitate.
