Question 41 of 43advanced✨ CreateEssay5 marks

Compare atoms and ions of any three elements. Show the number of electrons before and after ion formation using bar graphs.

Correct Answer

Comparison of atoms and ions of three elements:

1. Sodium (Na):

  • Atom: Has 11 electrons (electronic configuration: 2, 8, 1)
  • Ion (Na⁺): Has 10 electrons (electronic configuration: 2, 8)
  • Sodium loses 1 valence electron to achieve stable octet, forming a cation.

2. Magnesium (Mg):

  • Atom: Has 12 electrons (electronic configuration: 2, 8, 2)
  • Ion (Mg²⁺): Has 10 electrons (electronic configuration: 2, 8)
  • Magnesium loses 2 valence electrons to achieve stable octet, forming a cation.

3. Chlorine (Cl):

  • Atom: Has 17 electrons (electronic configuration: 2, 8, 7)
  • Ion (Cl⁻): Has 18 electrons (electronic configuration: 2, 8, 8)
  • Chlorine gains 1 electron to achieve stable octet, forming an anion.

Bar Graph Representation:

Number of Electrons 18 | ■ | ■ 17 | ■ ■ | ■ ■ 12 | ■ ■ ■ | ■ ■ ■ 11 | ■ ■ ■ ■ | ■ ■ ■ ■ 10 | ■ ■ ■ ■ |_____________ Na Mg Cl ■ ■ ■ = Atom ■ ■ ■ = Ion

Na: Atom=11, Ion=10 Mg: Atom=12, Ion=10 Cl: Atom=17, Ion=18

Exercise: The Journey Beyond | Q: 2 | (Page 22)
For More Understanding

Explanation

The question asks students to compare atoms and ions of three elements using bar graphs. From the context, we learn that atoms with less than 4 valence electrons (like Na and Mg) donate electrons to form cations, while atoms with more than 4 valence electrons (like Cl) gain electrons to form anions. The context explicitly mentions sodium (atomic number 11), magnesium forming Mg²⁺ by giving two electrons, and chlorine taking one electron to form Cl⁻. The bar graph visually represents the change in electron count during ion formation, showing that cations have fewer electrons than their atoms while anions have more.

Solution Steps

  1. Step 1: Select three elements - Sodium (Na), Magnesium (Mg), and Chlorine (Cl) based on context references.

  2. Step 2: Determine electrons in neutral atoms using atomic numbers: Na=11, Mg=12, Cl=17.

  3. Step 3: Calculate electrons in ions: Na⁺=10 (loses 1), Mg²⁺=10 (loses 2), Cl⁻=18 (gains 1).

  4. Step 4: Compare - cations have fewer electrons than atoms; anions have more electrons than atoms.

  5. Step 5: Represent data using bar graph with two bars per element showing electron count before and after ion formation.

PreviousNext