PAK NAVY FMT Chemistry Quiz 4
Results
PASSED!
FAIL!
#1. The electrolyte used in lead storage battery is:
#2. Catalyst increases the rate of reaction by lowering the:
#3. According to Le Chatelier’s principle, adding more reactants shifts the equilibrium to the:
#4. The unit of equilibrium constant Kc for reaction H2 + I2 2HI is:
#5. Solubility product (Ksp) applies to:
#6. Common ion effect suppresses the ionization of a:
#7. Which indicator gives pink color in basic medium?
#8. Conjugate acid of H2O is:
#9. Conjugate base of H2O is:
#10. Heat of neutralization of a strong acid and a strong base is approximately:
#11. Hess’s Law is used to calculate:
#12. Standard condition for thermodynamic measurements is temperature of:
#13. The formula of plaster of Paris is:
#14. Chemical formula of baking soda is:
#15. Chemical formula of washing soda is:
#16. Chemical formula of quicklime is:
#17. Chemical formula of slaked lime is:
#18. Bleaching powder is chemically:
#19. LPG (Liquefied Petroleum Gas) mainly contains:
#20. CNG (Compressed Natural Gas) mainly contains:
#21. The process of heating ore in the presence of excess air is called:
#22. Heating of ore in the absence of air is called:
#23. Brass is an alloy of:
#24. Bronze is an alloy of:
#25. Stainless steel contains steel mixed with:
#26. Which gas turns lime water milky?
#27. Which gas has the odor of rotten eggs?
#28. Ammonia gas turns red litmus paper:
#29. The process used industrially to manufacture ammonia is:
#30. The industrial process used for manufacturing nitric acid is:
Chemistry Quiz 4: Chemical Reactions and Equations
Discover how substances change during chemical reactions and learn to recognise common reaction patterns.
What Happens During a Chemical Reaction?
Pak Navy FMT Chemistry Quiz 4 covers chemical reactions, chemical equations, balancing equations, and common reaction types. This article is intended for students who want to revise introductory chemistry while preparing for the Pakistan Navy Female Medical Technician initial test.
A chemical reaction occurs when substances are transformed into new substances. During a reaction, atoms are rearranged as chemical bonds break and new bonds form. Understanding this process helps students interpret chemical equations and identify reaction types.
Key Learning Areas
🔹 Reactants and products
🔹 Balanced chemical equations
🔹 Combination and decomposition reactions
🔹 Displacement reactions
🔹 Oxidation and reduction basics
Reactants Versus Products
Reactants are the starting substances in a chemical reaction. Products are the substances formed by the reaction. In a chemical equation, reactants are written on the left side and products on the right side.
Reactants → Products
Example: 2H₂ + O₂ → 2H₂O
Why Must Equations Be Balanced?
Chemical equations must be balanced because atoms are conserved during ordinary chemical reactions. This means the number of atoms of each element must be the same on both sides of the equation.
To balance an equation, change the coefficients placed before chemical formulas. Do not change the subscripts inside a formula, because doing so would change the identity of the substance.
Worked Example
Unbalanced equation:
H₂ + O₂ → H₂O
Balanced equation:
2H₂ + O₂ → 2H₂O
Both sides now contain four hydrogen atoms and two oxygen atoms.
Common Types of Chemical Reactions
1. Combination Reaction
Two or more substances combine to form a single product.
Example: 2H₂ + O₂ → 2H₂O
2. Decomposition Reaction
A compound breaks down into two or more simpler substances.
Example: CaCO₃ → CaO + CO₂, when heated under suitable conditions.
3. Displacement Reaction
A more reactive element replaces a less reactive element in a compound.
Example: Zn + CuSO₄ → ZnSO₄ + Cu
How to Prepare for Reaction-Based MCQs
Start by identifying the reactants and products. Next, count the atoms on both sides of the equation. Finally, determine whether the equation represents combination, decomposition, displacement, or another reaction type.
Practise with different equations and always check that each element has the same number of atoms on both sides of a balanced equation.
Before You Start the Quiz
- Review the law of conservation of mass.
- Memorise the meaning of reactants and products.
- Practise balancing simple equations.
- Learn how to distinguish common reaction types.
Remember: Understanding the reaction pattern is more helpful than memorising equations without understanding them.
Educational notice: This article is an independent study resource and is not an official Pakistan Navy FMT examination paper. Actual test questions and timings may differ.