What is inside the atom — Practice Quiz

8

Step 1: The maximum number of electrons in any shell is given by the formula 2n². Step 2: For L shell, n = 2 (as it is the second shell from nucleus). Step 3: Using the formula: 2n² = 2 × (2)² = 2 × 4 = 8 electrons. Step 4: K shell (n=1) holds 2 electrons, L shell (n=2) holds 8 electrons. Step 5: M shell would hold 18 electrons and N shell would hold 32 electrons using the same formula.

4

Step 1: Carbon has atomic number 6, so it has 6 electrons. Step 2: Electron distribution is 2, 4 (2 in K shell, 4 in L shell). Step 3: The outermost shell (L shell) has 4 electrons. Step 4: Valency is the number of electrons in the outermost shell that can participate in bonding. Step 5: Since carbon has 4 electrons in its outer shell, its valency is 4, making it capable of forming 4 bonds.

Neon

Step 1: Noble gases have complete outer electron shells, making them very stable. Step 2: Neon has electron configuration 2, 8 - its outer L shell is completely filled with 8 electrons. Step 3: This complete octet makes neon chemically unreactive or inert. Step 4: Sodium (2,8,1), chlorine (2,8,7), and magnesium (2,8,2) all have incomplete outer shells. Step 5: Other noble gases include helium (2), argon (2,8,8), showing the pattern of complete outer shells.

Number of protons

Step 1: Atomic number (Z) is the defining characteristic of an element. Step 2: It represents the number of protons in the nucleus of an atom. Step 3: Every atom of the same element has the same number of protons, making atomic number unique for each element. Step 4: In a neutral atom, number of electrons equals number of protons, but atomic number specifically refers to protons. Step 5: Neutrons can vary (forming isotopes), but proton number remains constant for an element.