Chemical Bonding

How the real exam tests it

Questions from real CSCA papers that test this concept. Work each one out before you open the answer.

1. CSCA Chemistry December 2025 Past Paper
   Which group of substances contains the same type of chemical bond(s) throughout? ( )
   • A. NaCl and HCl
   • B. O₂ and H₂
   • C. HNO₃ and NH₄NO₃
   • D. NaOH and KCl
   Show answer & solution

   Answer: B

   Answer: B O₂ and H₂ are both nonmetal molecules held together only by covalent bonds. NaCl is ionic while HCl is covalent; HNO₃ is covalent while NH₄NO₃ has ionic and covalent bonds; NaOH has ionic and covalent bonds while KCl is only ionic.
   See it in the full CSCA Chemistry December 2025 Past Paper
2. CSCA Chemistry April 2026 Past Paper
   Among the following substances, the one that contains ionic bonds is ( ).
   • A. NaCl
   • B. CO
   • C. $\mathrm{N_{2}}$
   • D. $\mathrm{H_{2}O}$
   Show answer & solution

   Answer: A

   Answer: A NaCl is composed of $\mathrm{Na^{+}}$ and $\mathrm{Cl^{-}}$ and contains ionic bonds.
   Take the full CSCA Chemistry April 2026 Past Paper — timed & graded
3. CSCA Chemistry March 2026 Past Paper
   In which pair are the bond types not entirely the same?
   • A．MgO and $\mathrm { CaCl } _ { 2 }$
   • B．$\mathrm { H } _ { 2 } \mathrm { O }$ and $\mathrm { CO } _ { 2 }$
   • C．$\mathrm { Na } _ { 2 } \mathrm { SO } _ { 4 }$ and KCl
   • D．$\mathrm { NH } _ { 4 } \mathrm { Cl }$ and NaCl
   Show answer & solution

   Answer: D

   $\mathrm { NH } _ { 4 } \mathrm { Cl }$ : ionic + covalent bonds. NaCl: ionic only. Different types. Answer: D.
   Take the full CSCA Chemistry March 2026 Past Paper — timed & graded