Start learning →

DSSSB TGT Chemical Reactions and Equations — practice questions

Explore 17 free Chemical Reactions and Equations questions in DSSSB TGT Chemistry. Open each question or exercise to read its content, reference answers and available explanation.

Practise Chemical Reactions and Equations with Quill →

Chemical Reactions and Equations questions and exercises with answers

Showing questions 1–17 of 17.

Which observation does NOT necessarily indicate a chemical reaction?Read the answer and worked solution →Balance: H₂ + O₂ → H₂O.Read the answer and worked solution →Which principle requires us to balance chemical equations?Read the answer and worked solution →Balance: Fe + H₂O → Fe₃O₄ + H₂.Read the answer and worked solution →In Zn + 2 HCl → ZnCl₂ + H₂, the state symbol for HCl in solution is:Read the answer and worked solution →CaCO₃ → CaO + CO₂ is an example of which type of reaction?Read the answer and worked solution →In Fe + CuSO₄ → FeSO₄ + Cu, what kind of reaction is this?Read the answer and worked solution →2 H₂ + O₂ → 2 H₂O is a:Read the answer and worked solution →In the reaction Na₂SO₄ + BaCl₂ → BaSO₄ + 2 NaCl, what is observed?Read the answer and worked solution →Which of these is an endothermic reaction?Read the answer and worked solution →Which reaction does NOT need heat to proceed?Read the answer and worked solution →In the reaction CuO + H₂ → Cu + H₂O, the substance that is reduced is:Read the answer and worked solution →A reaction in which one substance is oxidised and another reduced is called a:Read the answer and worked solution →Rusting of iron requires which two conditions?Read the answer and worked solution →Chips packets are flushed with nitrogen mainly to:Read the answer and worked solution →In ZnO + C → Zn + CO, the reducing agent is:Read the answer and worked solution →Silver objects turn black on long exposure to air mainly because:Read the answer and worked solution →

Worked practice questions

Which observation does NOT necessarily indicate a chemical reaction?

  1. A gas is evolved
  2. Colour changes
  3. A precipitate forms
  4. Volume decreases
Show answer and solution

Correct answer: D. Volume decreases

Volume change can happen with purely physical processes (e.g., cooling). The other three are characteristic signs of a chemical change.

Open this question →

Balance: H₂ + O₂ → H₂O.

  1. 2 H₂ + 2 O₂ → 2 H₂O
  2. H₂ + O₂ → H₂O
  3. 2 H₂ + O₂ → 2 H₂O
  4. H₂ + 2 O₂ → 2 H₂O
Show answer and solution

Correct answer: C. 2 H₂ + O₂ → 2 H₂O

Two waters need 4 H and 2 O. Left side: 2 H₂ gives 4 H, and O₂ gives 2 O. So 2 H₂ + O₂ → 2 H₂O.

Open this question →

Which principle requires us to balance chemical equations?

  1. Conservation of mass
  2. Conservation of energy
  3. Conservation of momentum
  4. Conservation of charge
Show answer and solution

Correct answer: A. Conservation of mass

Atoms are neither created nor destroyed in chemical reactions so the count of each kind of atom (and hence the total mass) must match on both sides.

Open this question →

How to practise

  1. Choose a Chemical Reactions and Equations question and try to work out your answer.
  2. Open the question to check the correct answer and read its worked solution.
  3. Continue in the app for bite-sized lessons, explanations and review with Quill. You can start without creating an account.

More Chemistry topics

Alcohols Phenols EthersAlkenesChemical EquilibriumClassification of Elements and PeriodicityOrganic Chemistryp-Block Elementsp-Block Elements (Groups 15-18)Polymers