Summary & Quick Quiz ലായനികൾ
The whole chapter on one page: solutions in five pictures, the key boxes of the textbook, every rule you need – solute and solvent, like dissolves like, mass percentage, saturated, unsaturated and supersaturated solutions, solubility and its factors, true solutions, colloids and suspensions, the types of colloids and food additives – a mass-percentage calculator, a mixture sorter, the mistakes to avoid, flashcards, a scored quiz and your study checklist.
1. The chapter in five pictures
2. The key boxes of the textbook
Mixtures that show the same properties in all parts are homogeneous mixtures. A solution is a homogeneous mixture of solute and solvent. – page 3
The amount of solute dissolved in a definite amount of solution. Little solute – a dilute solution; more solute – a concentrated solution. – page 4
A solution in which the maximum amount of solute has dissolved at a given temperature. – page 5
A solution with less solute than is needed to saturate it at that temperature. – page 5
A solution with more solute dissolved than is needed to saturate it at that temperature – unstable. – page 5
The amount of solute in grams needed to saturate 100 g of the solvent at a given temperature. – page 6
916 g of pure gold in 1000 g of ornament, the rest silver and copper – a solid solution (916 = 22 carat). – page 3
Water molecules surround Na+ (O side, δ−, towards it) and Cl− (H side, δ+, towards it): hydrated ions – an ionic solution. – page 3
ppm = parts per 106 parts: chlorine in drinking water 4 ppm; oxygen in sea water 5.8 ppm; CO2 in air 270 ppm → 414 ppm. Also volume %, molarity, molality. – page 4
Na2SO4·10H2O: 47.6 g at 0 °C, rising to 49.7 g at 32.4 °C, then decreasing – anomalous solubility. – page 6
True solution 0.01–1 nm; colloid 1–1000 nm; suspension more than 1000 nm. – page 7
An emulsion of vegetable oil with egg white (or milk) and vinegar – keep it fresh and cold; spoilt mayonnaise is a food-safety risk. – page 8
Keep the particles in artificial drinks from settling: brominated vegetable oil, sucrose acetate isobutyrate, glyceryl ester of rosin. – page 8
Carbonated drinks with CO2, colours, preservatives and sweeteners (aspartame, saccharin, high-fructose corn syrup); the book lists their health concerns. – page 8
3. Facts & rules
📐 Facts & rules card
mass percentage = (mass of solute ÷ mass of solution) × 100
solubility = grams of solute that saturate 100 g of solvent at a given temperature
Solute, solvent, solution ലീനം · ലായകം · ലായനി
The component in the smaller amount is the solute, the one in the larger amount the solvent; in an aqueous solution (ജലീയ ലായനി) water is always the solvent. The solution usually has the state of its solvent: solid solutions (ഖരലായനി) – brass (zinc 34 % in copper 66 %), 916 gold; liquid solutions (ദ്രാവകലായനി) – salt water, soda water, alcohol in water; gaseous solutions (വാതകലായനി) – air (nitrogen 78 % is the solvent). The components do not react chemically.
Like dissolves like (സമാനമായത് സമാനമായതിനെ ലയിപ്പിക്കും): polar (പോളാർ) and ionic solutes dissolve in polar solvents – salt in water; non-polar (നോൺപോളാർ) substances – enamel paint, grease, kerosene – in non-polar organic solvents (ഓർഗാനിക് ലായകങ്ങൾ) such as turpentine. Water dissolves so many substances that it is called the universal solvent (സാർവിക ലായകം).
Mass percentage മാസ് പെർസെന്റേജ്
- Forward: 10 g salt + 90 g water → 10 ÷ 100 × 100 = 10 %; 2 g + 18 g water → 2 ÷ 20 × 100 = 10 %.
- Meaning: a 15 % salt solution has 15 g of salt in every 100 g of solution.
- Reverse: solute = % × solution ÷ 100; solution = solute × 100 ÷ %; then water = solution − solute (1 mL of water ≈ 1 g).
Saturated, unsaturated, supersaturated പൂരിത · അപൂരിത · അതിപൂരിത ലായനി
Test: drop in one crystal of the solute. It dissolves → unsaturated; it stays → saturated; crystals grow on it → supersaturated.
Factors of solubility ലേയത്വം · ലേയത്വ കർവ്
| Factor | What the book shows |
|---|---|
| Nature of the solute | in 50 mL of water much more NaCl dissolves than NaHCO3 |
| Nature of the solvent | NaCl dissolves well in water, little in alcohol, not in kerosene |
| Temperature | most solids dissolve more when hot (KNO3 steeply); NaCl changes very little; calcium sulphate decreases slightly; Glauber’s salt rises to 32.4 °C and then falls. Gases dissolve less when hot. |
| Pressure (gases) | more gas dissolves at higher pressure – soda is made under high pressure and fizzes when opened |
True solution, colloid, suspension യഥാർഥ ലായനി · കൊളോയിഡുകൾ · സസ്പെൻഷൻ
| Property | True solution | Colloid | Suspension |
|---|---|---|---|
| Particle size | 0.01–1 nm | 1–1000 nm | more than 1000 nm |
| Particles seen? | no, not even with a microscope | not with the naked eye | yes |
| Settle on standing? | no | no | yes |
| Filter paper | passes through | passes through | left as a residue |
| Path of a light beam | not seen | seen – Tyndall effect (ടിൻഡൽ പ്രഭാവം) | seen |
| Kind of mixture | homogeneous | looks homogeneous | heterogeneous (ഭിന്നാത്മക മിശ്രിതം) |
The sorter uses only what you can see: if the particles settle or are left on filter paper → suspension; otherwise, if the beam is seen → colloid; otherwise → true solution.
Types of colloids ഡിസ്പേർസ്ഡ് ഫേസ് · ഡിസ്പേർഷൻ മീഡിയം
| Dispersed phase | Dispersion medium | Type | Examples |
|---|---|---|---|
| solid | solid | solid sol | gems |
| liquid | solid | gel | butter, jam, cheese |
| gas | solid | solid foam | rubber (foam) mattress |
| solid | liquid | sol | kanji vellam (rice water) |
| liquid | liquid | emulsion | milk, paint, mayonnaise (മയോണൈസ്) |
| gas | liquid | foam | soap lather |
| solid | gas | aerosol | smoke, dust |
| liquid | gas | liquid aerosol | mist, clouds |
Drinks and food additives കൃത്രിമ പാനീയങ്ങൾ · സ്റ്റെബിലൈസറുകൾ · പ്രിസർവേറ്റീവുകൾ
Natural drinks – pure water, buttermilk, lemon water, tender coconut water, fresh fruit juices – keep only for a short time. Stabilisers stop particles settling in artificial drinks; preservatives keep food from spoiling (vinegar, salt). Table 6.5: tartrazine – yellow; erythrosine – red; indigo carmine – blue; vanillin – flavour; phosphoric acid – sourness in soft drinks; allyl hexanoate – pineapple flavour; sodium benzoate – sauces, salads, soft drinks, against yeast and moulds; sorbic acid – cheese, cake, salad, against moulds.
- Dividing by the mass of the solvent. Mass percentage uses the mass of the solution (solute + solvent): 12 g in 68 g water is 12 ÷ 80, not 12 ÷ 68.
- Saying the solvent is always a liquid. In brass the solvent is copper (a solid); in air it is nitrogen (a gas).
- Calling a saturated solution “concentrated” and an unsaturated one “dilute”. Saturation compares with the solubility at a stated temperature; a saturated solution of a poorly soluble salt is still dilute.
- Saying gases dissolve more when water is warmed. They dissolve less – warm soda goes flat, fish suffer in warm water.
- Saying every salt dissolves more when heated. NaCl barely changes; calcium sulphate, and Glauber’s salt above 32.4 °C, become less soluble.
- Thinking colloid particles settle or can be filtered. They do not – suspension particles do.
- Mixing up dissolving and melting. Sugar in tea dissolves (spreads into the solvent); ice on a plate melts (solid → liquid on heating).
- Thinking every clear liquid is a true solution. Some colloids look clear but show the Tyndall effect in a torch beam.
4. Flashcards
Click a card to flip it.
5. Scored quiz
Answer all sixteen, then press Check my answers. Each wrong answer shows the page to revise. For number answers type only the number.
6. Your study checklist
Ticks come from “Mark this page as completed” at the bottom of each page.
Next: the model test paper ▶ – attempt it on paper with a timer first, then check with the solved paper.