- Period 3 and Their Oxides

Amphoteric

Acts as both an acid and a base

What is the reaction between Na and Water?

2Na(s) + 2H₂O(l) →2NaOH(aq) + H₂(g)

What is the reaction between Mg and COLD WATER?

Mg(s) + 2H₂O(l) →Mg(OH)₂(s) + H₂(g)

What is the reaction between Mg and STEAM?

Mg(s) + H₂O(g) →MgO(s) + H₂(g)

What's observed when Mg reacts with COLD WATER?

fizzing/gas evolved

What's observed when Mg reacts with STEAM?

White Flame

White Solid

What's observed when Na reacts with water?

Gas evolved

Why does Na react more readily with cold water than Mg?

Na reacts by losing ONE electron whereas Mg reacts by losing TWO electrons

Why does Sulfur have a higher melting point than Phosphorus?

Sulfur exists as S₈ whereas Phosphorus exists as P₄, S₈ is the larger molecule therefore will have stronger Van der Waals forces between molecules, so more heat energy will be required to break them

Why does Silicon have a higher melting point than Phosphorus?

Si exists in a GIANT covalent lattice, whereas Phosphorus exists in a SIMPLE covalent. Si has strong covalent bonds that need to be overcome, whereas Phosphorus has weak Van der Waals forces between molecules that require less energy to break.

Why does Magnesium have a higher melting point than Sodium?

Mg has stronger metallic bonds compared to Na as it has more delocalised electrons due to its ions existing as a Mg²⁺, whereas Na ions exist as Na⁻.

Why is the melting point of Carbon high?

Carbon exists as a giant covalent lattice. There are many strong covalent bonds that require a lot of energy to break

What's the reaction of Na with Oxygen?

4Na(s) + O₂(g) → 2Na₂O(s)

What's observed in the reaction of Na with Oxygen?

Orange/Yellow flame

Yellow solid

reacts readily in air

What's the reaction between Mg and Oxygen?

2Mg(s) + O₂(g)→2MgO(s)

What's observed in the reaction of Mg with Oxygen?

White flame

White solid

reacts readily in air

What's the reaction between Al and Oxygen?

4Al(s) + 3O₂(g)→2Al₂O₃(s)

What's observed in the reaction of Al with Oxygen?

reacts slowly

What's the reaction between Si and Oxygen?

Si(s) + O₂(g) →SiO₂(s)

What's observed in the reaction of Si with Oxygen?

reacts slowly

What's the reaction between P₄ and Oxygen?

P₄(s) + 5O₂(g)→P₄O₁₀(s)

What's observed in the reaction of P₄ with Oxygen?

White flame

White smoke

How is P₄ stored and why?

In oil or under water

it ignites spontaneously in air

What is the oxidation state of the resulting Phosphorus after the reaction with oxygen?

+5

What's the reaction between S and Oxygen?

S(s) + O₂(g) →SO₂(g)

What's observed in the reaction of S with Oxygen?

Blue flame

Choking gas

What's the reaction between Na₂O(s) and Water? What is the resulting pH?

Na₂O(s) + H₂O(l) →2NaOH(aq)

Very Alkali: 12-14

What's the reaction between MgO(s) and Water? What is the resulting pH?

MgO(s) + H₂O(l)→Mg(OH)₂(aq)

Alkali (sparingly soluble): 9-10

What's the reaction between Al₂O₃ and Water? What is the resulting pH?

NO REACTION

pH: 7

What's the reaction between SiO₂ and Water? What is the resulting pH?

NO REACTION

pH: 7

What's the reaction between P₄O₁₀ and Water? What is the resulting pH?

P₄O₁₀(s) + 6H₂O(l)→4H₃PO₄(aq)

Phosphoric Acid: 1

What is the reaction between SO₂ and Water? What is the resulting pH?

SO₂(g) + H₂O(l)→H₂SO₃

Sulfuric (IV) Acid: 1

What's the reaction between SO₃ and Water? What is the resulting pH?

SO₃(g) + H₂O(l)→H₂SO₄

Sulfuric (VI) Acid: 0

What are the stages for the full dissociation of H₃PO₄?

H₃PO₄ ⇌ H₂PO₄⁻ + H⁺

H₂PO₄⁻⇌HPO₄²⁻ + H⁺

HPO₄²⁻⇌PO₄³⁻ + H⁺

What are the stages for the full dissociation of H₂SO₄?

H₂SO₄⇌HSO₄⁻+ H⁺

HSO₄⁻⇌SO₄²⁻+ H⁺

What is the reaction between Na₂O and HCl

Na₂O(s) + 2HCl(aq) → 2NaCl(aq) + H₂O(l)

What is the reaction between Na₂O and H₃PO₄?

3Na₂O(s) + 2H₃PO₄(aq) →2Na₃PO₄(aq) + 3H₂O(l)

What is the reaction between Na₂O and H₂SO₄?

Na₂O(s) + H₂SO₄(aq) →Na₂SO₄(aq) + H₂O(l)

What is the reaction between MgO and H₃PO₄?

3MgO(s) + 2H₃PO₄(aq) →(Mg)₃(PO₄)₂(aq) + 3H₂O(l)

What is the reaction between MgO and H₂SO₄?

MgO(s) + H₂SO₄(aq)→MgSO₄(aq) + H₂O(l)

What is the reaction between MgO and HCl?

MgO(s) + 2HCl(aq)→MgCl₂(aq) + H₂O(l)

What is the reaction of Al₂O₃ with HCl?

Al₂O₃(s) + 6HCl(aq)→2AlCl₃(aq) + 3H₂O(l)

What is the reaction of Al₂O₃ and NaOH?

Al₂O₃(s) + 2NaOH(aq) + 3H₂O(l)→2NaAl(OH)₄(aq)

What is the reaction between SiO₂ and NaOH?

SiO₂(s) + 2NaOH(aq) →Na₂SiO₃(aq) + H₂O(l)

what is the reaction between SiO₂ and Mg(OH)₂?

SiO₂(s) +Mg(OH)₂(aq)→MgSiO₃(aq) + H₂O(l)

What is the reaction between SiO₂ and Ca(OH)₂?

SiO₂(s) + Ca(OH)₂(aq)→CaSiO₃(aq) + H₂O(l)

What is the reaction between P₄O₁₀ and NaOH?

P₄O₁₀(s) + 12NaOH(aq) →4Na₃PO₄(aq) + 6H₂O(l)

What is the reaction between P₄O₁₀ and Ca(OH)₂?

P₄O₁₀(s) + 6Ca(OH)₂(aq)→2Ca₃(PO₄)₂(aq) + 6H₂O(l)

What is the reaction between SO₃ and NaOH?

SO₃(s) + 2NaOH(aq) →Na₂SO₄(aq) + H₂O(l)

What is the reaction between SO₂ and NaOH?

SO₂(g) + 2NaOH(aq) →Na₂SO₃(aq) + H₂O(l)