Track quiz
Ten quick questions, one or two for each lesson. Use the table if you get stuck.
| Idea | Remember |
|---|---|
| New substance | A chemical reaction makes a new substance with new properties. The starting substances are reactants. The new substances are products. |
| Words to formulae | A word equation names reactants and products in words. A skeleton equation writes the same names as formulae. The arrow means gives. |
| Balancing | Atoms only rearrange in a reaction. Each atom's count must match on both sides. A coefficient multiplies one whole formula. |
| Combination | A combination reaction joins reactants into one product. The balanced equation fixes the exact proportion. Extra reactant waits, unused. |
| Decomposition | A decomposition reaction splits one reactant into two or more products. Heat, light or electricity usually gives the push. |
| Displacement | In displacement, a free element takes another's place in a compound. The pushed-out element becomes free. Whether it happens is measured, not guessed. In double displacement, two compounds swap partners. A solid that does not dissolve falls out as a precipitate. |
| Redox | Gaining oxygen is oxidation. Losing oxygen is reduction. Both happen together in one redox reaction. |
| Slow reactions | Corrosion and rancidity are slow reactions with oxygen. Rusting needs both oxygen and moisture. Take an ingredient away and the reaction slows. |
| Writing the swapped formulas | In a double displacement reaction, two compounds swap partners. Each new formula comes from crossing the charges, then cutting down. A solid that does not dissolve is a precipitate. |
Milk sets into curd. What makes this a chemical change?
Which is the skeleton equation for iron and sulphur giving iron sulphide?
Na + Cl₂ → NaCl is unbalanced. Which sentence balances it?
4 H₂ meet 3 O₂ in 2H₂ + O₂ → 2H₂O. What is left?
Silver chloride turns grey in sunlight. What push caused it?
A zinc strip is put in iron sulphate solution. What happens?
Magnesium sulphate solution is poured into sodium hydroxide solution. What is seen?
In PbO + H₂ → Pb + H₂O, which substance is reduced?
Calcium nitrate meets potassium carbonate in water. The partners swap. Which new compound is the solid?
A bag of cashew nuts is sealed with nitrogen inside. Why?
Chapter 1 is in your Class 10 book, Science. It goes further into each reaction shape. You have balanced equations, and sorted reactions by their shapes.
Next comes Acids, Bases and Salts. Every acid equation in it is written and balanced the same way.