Higher Secondary Certificate Examination (Bangladesh) · Chemistry

Chemical Equilibrium, Energetics and Environmental Chemistry

35 practice questions, each with the answer and an explanation.

Practise Chemical Equilibrium, Energetics and Environmental Chemistry now

Random questions from this topic, one at a time. You see the answer and the explanation straight after each one.

All 35 questions

  1. What is the relation between equilibrium constants K_p and K_c for a general gaseous reaction?
  2. For the reaction N2(g) + 3H2(g) <=> 2NH3(g), what is the value of Delta n?
  3. According to Le Chatelier's Principle, how does increasing total pressure affect the equilibrium position of N2(g) + 3H2(g) <=> 2NH3(g)?
  4. How does increasing temperature affect the equilibrium of an exothermic reaction (Delta H < 0)?
  5. What is the pH of a 0.01 M aqueous solution of Hydrochloric Acid (HCl)?
  6. What is the pH of a 0.001 M aqueous solution of Sodium Hydroxide (NaOH) at 25 degrees Celsius?
  7. What is the ion-product constant of pure water (K_w) at 25 degrees Celsius?
  8. What is the Henderson-Hasselbalch equation for calculating the pH of an acidic buffer solution?
  9. Which pair of substances forms an effective acidic buffer solution in aqueous medium?
  10. What is the relationship between solubility s and solubility product K_sp for a sparingly soluble salt of type AB2 (like PbCl2)? (Hard)
  11. What phenomenon describes the decrease in solubility of a sparingly soluble salt when a soluble electrolyte containing an identical ion is added?
  12. According to Hess's Law of Constant Heat Summation, what is true about the enthalpy change of a chemical reaction?
  13. What is the unit of the rate constant k for a first-order chemical reaction?
  14. How does adding a positive catalyst increase the rate of a chemical reaction?
  15. According to the Arrhenius equation k = A e^(-E_a / RT), what does plotting ln(k) against 1/T yield? (Hard)
  16. What is the primary gas responsible for the enhanced greenhouse effect in Earth's atmosphere?
  17. What is the critical threshold value of pH below which atmospheric precipitation is classified as acid rain?
  18. Which two acidic oxides are the primary causes of acid rain?
  19. What does the parameter Biochemical Oxygen Demand (BOD) measure in water quality testing?
  20. What happens to Chemical Oxygen Demand (COD) compared to Biochemical Oxygen Demand (BOD) for a given polluted wastewater sample? (Hard)
  21. What is the maximum permissible limit of arsenic in drinking water according to Bangladesh national standards (DoE)?
  22. Which class of synthetic chemicals is primarily responsible for catalytic destruction of the stratospheric ozone layer?
  23. What is the primary chemical oxidant that produces photochemical smog in urban atmospheres?
  24. What is the enthalpy change of a reaction Delta H in terms of bond enthalpies of reactants and products? (Hard)
  25. What is the standard state temperature and pressure (STP) defined in classical chemistry for gas volume calculations?
  26. What is the volume occupied by one mole of any ideal gas at standard temperature and pressure (STP, 0 deg C and 1 atm)?
  27. According to Graham's Law of Effusion, what is the ratio of rates of effusion of two gases r1 / r2?
  28. What is the ratio of effusion rate of Hydrogen gas (H2, M = 2) to Oxygen gas (O2, M = 32)?
  29. In the van der Waals equation of real gases [P + a n^2 / V^2](V - n b) = n R T, what does parameter 'a' correct for? (Hard)
  30. In the van der Waals equation of real gases, what does the parameter 'b' represent?
  31. Under what physical conditions does a real gas behave most like an ideal gas?
  32. What is the compressibility factor Z for an ideal gas at all temperatures and pressures?
  33. Which property defines an open thermodynamic system?
  34. What is an intensive thermodynamic property of a system?
  35. What is the standard enthalpy of formation Delta H_f^\circ of a pure element in its most stable reference state at 298 K?

Keep practising

More Higher Secondary Certificate Examination (Bangladesh) topics

All Higher Secondary Certificate Examination (Bangladesh) practice →

Ready for the full Higher Secondary Certificate Examination (Bangladesh) test?

Take a mock testHigher Secondary Certificate Examination (Bangladesh) hub