Expert Chemistry Tutoring

MS1:

- Definition of electronegativity (1)

- Trend across a period: increases from left to right (1)

- Trend down a group: decreases from top to bottom (1)

MS2:

- Presence of mobile ions (free electrons) (1)

- Formation of positive and negative ions upon loss and gain of electrons (1)

- Freedom of movement of ions facilitates flow of current (1)

MS3:

- Formula: Atomic mass = (Abundance of isotope 1 × Relative atomic mass of isotope 1) + (Abundance of isotope 2 × Relative atomic mass of isotope 2) (1)

- Substitution: 12.0 × 0.9223 + 13.0 × 0.0467 = 12.1 (1)

- Final answer: 12.1 (1)

MS4:

- Oganesson (Og) (1)

MS5:

- Layers of atoms can slide past each other (1)

- Strong metallic bonds within layers (1)

MS6:

- Products: KCl (1)

MS7:

- Metallic bonding (1)

- Electrons are delocalized and move freely (1)

- Forms a "sea" of electrons, giving metals their characteristic properties (e.g., malleability, ductility, conductivity) (1)

MS8:

- Physical differences:

- Metals: shiny, good conductors, malleable (e.g., copper) (1)

- Non-metals: dull, poor conductors, brittle (e.g., carbon) (1)

- Chemical differences:

- Metals: form basic oxides, react with acids (1)

- Non-metals: form acidic oxides, react with bases (1)

MS9:

- Formula for mass: Mass of NaCl = Mass of Na × (Relative atomic mass of NaCl / Relative atomic mass of Na) (1)

- Mass of NaCl = 2.3 g × (58.5 / 23) = 5.85 g (1)

- Final answer: 5.85 g (1)

MS10:

- Reactivity increases:

- Larger atomic size, leading to weaker attraction to outer electrons (1)

- Melting point decreases:

- Weaker metallic bonds due to larger atomic size (1)

- Appearance:

- Color changes from silvery to white (e.g., from lithium to potassium) (1)