Which of the following does NOT contain ionic bond?
A. CH₄
B. CaO
C. NaF
D. KCl
Answer: Option A
Solution (By JKSSB Mock Tests)
CH₄ (methane) has covalent bonds where carbon shares electrons with four hydrogen atoms. CaO (Ca²⁺ O²⁻), KCl, and NaF are ionic compounds formed by electron transfer between a metal and a non-metal. Ionic bonds form when electronegativity difference is large. Covalent bonds typically between non-metals with similar electronegativities.
Explanation:
PVC (polyvinyl chloride) is a polymer of vinyl chloride (CH₂=CHCl). It is used in pipes, electrical insulation, and flooring. It can be rigid (uPVC) or flexible with plasticizers. It is a thermoplastic. Chlorate/carbon/carbide are not correct expansions.
Explanation:
2H₂ + O₂ → 2H₂O is a combination reaction where two or more reactants combine to form a single product. A is decomposition. C is displacement. D is neutralization (also double displacement). Combination reactions are generally exothermic. Another example: C + O₂ → CO₂.
Explanation:
Limestone (CaCO₃) decomposes to CaO, which is a basic flux. It reacts with the acidic impurity silica (SiO₂) to form calcium silicate (CaSiO₃), a fusible slag: CaO + SiO₂ → CaSiO₃. Slag floats on molten iron and is tapped separately. Reduction is done by CO/coke. Flux makes gangue removal easier. Slag is used in cement, road building.
No comments yet. Be the first to start the discussion!