Periodicity (period 3) Flashcards
The reaction of Na with water
2Na(s) + 2H₂O(l) → 2NaOH (aq) + H₂(g)
Vigorous reaction, fizzing, molten ball on surface
The reaction of Mg with water
Mg + 2H₂O → Mg(OH)₂ + H₂ (magnesium hydroxide coats magnesium and stops further reaction)
Mg + H₂O(g) → MgO + H₂
Observation when sulfur reacts with oxygen
Blue flame (formation of SO₃ requires a catalyst)
Observation when aluminium, silicon, and phosphorous react with oxygen
White flame
Observation when sodium reacts with oxygen
Yellow flame
Observation when magnesium reacts with oxygen
Bright white flame and white powder formed
Structure and bonding of Na₂O
Giant ionic lattice, ionic bonding
Structure and bonding of MgO
Giant ionic lattice, ionic bonding. Higher charge density than Na₂O so higher melting point.
Structure and bonding of Al₂O₃
Giant ionic lattice, ionic bonding with covalent character due to high charge density of aluminium ion.
Structure and bonding of SiO₂
Giant covalent lattice, covalent bonding
Structure and bonding of P₄O₁₀
Simple covalent molecule, covalent bonding. Big molecule with lots of van der waals forces btwn molecules so high mpt.
Structure and bonding of SO₂
Simple covalent molecule, covalent bonding.
Which element in period 3 has the highest melting point?
Silicon, because it has a giant covalent lattice in which a lot of energy is required to break covalent bonds
What experiement would be used to test for ionic bonding?
Melt substance and check if it conducts electricity. Will not conduct in a solid state
Are metal oxides basic or acidic?
Basic
