S- and P-Block Elements MCQs for MDCAT Practice

Chemistry section, S- and P-Block Elements chapter. Up to eight free sample questions, each with the correct answer and a worked explanation. The full chapter opens in the app.

1. Question 1
   Which of the following tetrahalides does NOT undergo hydrolysis when treated with water?
   • ACCl4 (correct answer)
   • BSiCl4
   • CGeCl4
   • DSnCl4
   Correct answer: A

   Carbon tetrachloride (CCl4) is inert to hydrolysis due to the absence of vacant d-orbitals, unlike other Group 14 tetrahalides which readily hydrolyze.
2. Question 2
   Group 2 elements on reaction with oxygen form______ oxides.
   • APeroxide
   • BSuboxide
   • CNormal (correct answer)
   • DSuperoxide
   Correct answer: C

   Group 2 elements (alkaline earth metals) form normal oxides upon reaction with oxygen due to their characteristic +2 oxidation state.
3. Question 3
   (a) Define hydrides? Discuss ionic hydrides in detail. , (b) Discuss the peculiar behaviour of Beryllium.
   • AHydrides are binary compounds of hydrogen with other elements; ionic hydrides are formed by transition metals and are highly volatile liquids. (correct answer)
   • BHydrides are compounds of hydrogen with metals only; ionic hydrides are formed by d-block elements and are covalent in nature.
   • CHydrides are compounds of hydrogen with less electronegative elements; ionic hydrides are formed by alkali and alkaline earth metals and are crystalline solids with high melting points.
   • DHydrides are compounds of hydrogen with non-metals; ionic hydrides are formed by noble gases and are gases at room temperature.
   Correct answer: A

   This question probes the definition of hydrides and detailed knowledge of ionic hydrides, alongside the unique chemical properties of Beryllium.
4. Question 4
   Which of the following is metasilicic acid
   • AH2SiO3 (correct answer)
   • BH2SiO4
   • CH3AsO4
   • DH2SO4
   Correct answer: A

   Metasilicic acid, a common silicic acid, has the chemical formula $H_2SiO_3$. Understanding the nomenclature and formulas of oxyacids is crucial for s- and p-block elements.
5. Question 5
   Chile saltpetre has the chemical formula:
   • ANaNO3 (correct answer)
   • BKNO2
   • CNa2B4O7
   • DNa2CO3.H2O
   Correct answer: A

   Chile saltpetre, a naturally occurring mineral, is primarily sodium nitrate ($NaNO_3$). This question tests knowledge of common chemical compounds and their natural occurrences.
6. Question 6
   Color imparted to the Bunsen flame by strontium salt is:
   • AApple green
   • BBluish green
   • CCrimson red (correct answer)
   • DBrick red
   Correct answer: C

   Strontium salts produce a distinctive crimson red flame color in flame tests due to electron excitation and emission. Know other alkali/alkaline earth metal flame colors!
7. Question 7
   Moist ammonia may be dried by passing it through;
   • ACalcium oxide (correct answer)
   • BCalcium chloride
   • CCalcium hydroxide
   • DConc. Sulphuric acid
   Correct answer: A

   Ammonia is a basic gas and reacts with acidic drying agents. Calcium oxide (CaO) is a basic drying agent suitable for drying ammonia.
8. Question 8
   BeCl2 + LiAlH4 → X + LiCl + AlCl3
   • AX is lithium hydride (LiH)
   • BX is BeH2 (correct answer)
   • CX is beryllium dichloride dihydrate (BeCl2 · 2H2O)
   • DX is beryllium hydride (BeH2)
   Correct answer: B

   This question tests the reduction of beryllium chloride by lithium aluminum hydride to form beryllium hydride.

Read the full S- and P-Block Elements chapter notes: S- and P-Block Elements notes. Or browse every chapter.