The nutrient element essential for root development in plants is: MCQ with Answer and Explanation

Explanation:
Atomic number 12 = magnesium (Mg). Electronic configuration 2,8,2. It belongs to Group 2, Period 3. Sodium is 11, aluminium 13, potassium 19.

Explanation:
In BF₃, boron has 3 valence electrons and forms 3 covalent bonds with fluorine, resulting in only 6 electrons in its valence shell. It does not complete its octet, making it an electron-deficient molecule and a strong Lewis acid. NH₃, H₂O, and CH₄ all have complete octets.

Explanation:
Roasting: 2ZnS + 3O₂ → 2ZnO + 2SO₂. The oxide is then reduced with coke at high temperature: ZnO + C → Zn + CO. Alternatively, it can be leached with H₂SO₄ and electrolyzed.