A2: Period 3 Reactions

Question 1

Magnesium is heated with STEAM.

What do you OBSERVE and write the EQUATION

Answer 1

WHITE powder
WHITE light

Mg + H2O → MgO + H2

Question 2

Why does MAGNESIUM have a HIGHER melting point than SODIUM?

Answer 2

Magnesium ion (Mg2+) has higher charge than Na+

Metallic Bonding STRONGER

takes more energy to lose 2 electrons (Mg2+) than it does to lose one (Na+)

Question 3

Silicon Dioxide…

Structure and Bonding and PHYSICAL PROPERTIES of it

Answer 3

Giant Covalent
Bonding: Covalent
HARD and INSOLUBLE

Question 4

Phosphorus(V) Oxide;

Formula, Structure and Bonding? (4 marks)

Answer 4

P4 O10
MOLECULAR
Covalent
Dipole - Dipole forces BETWEEN MOLECULES

Question 5

Magnesium OXIDE; what type of Bonding is it?

Answer 5

ionic!!! There are 2 I’s in Magnesium Oxide!

MagnesIum OxIde

Question 6

Outline an experiment to demonstrate that magnesium oxide has ionic bonding:

Answer 6

MELT IT

MOLTEN OXIDE conducts electricity
LEARN THIS!!!

Question 7

Why is SILICON DIOXIDE…INSOLUBLE…in water?

Answer 7

Giant Covalent structure

Water CAN’T supply enough energy to break the COVALENT bonds

Question 8

Sodium with Water forms?

pH of it?

Observations?

Answer 8

2NaOH ➕ H2

ph: 12-14

formation of molten ball on surface and FIZZING

Question 9

Magnesium reacts with WATER to produce?

pH of it?

Answer 9

Mg(OH)2 ➕ H2

ph: 9 - 10

Question 10

Does Magnesium dissolve in water?

Answer 10

NO‼️‼️‼️

it is SPARINGLY soluble, hence,

NOT TOXIC

Question 11

What’s the formula for Phosphorous Acid⁉️

Answer 11

H3⃣ PO4⃣

Question 12

COLOUR of Na FLAME and what type of REACTION is it in AIR?

Answer 12

• Yellow 🔥

* Vigorous

Question 13

COLOUR of Mg FLAME and what type of REACTION is it in AIR?

Answer 13

• Brilliant White

* Vigorous

Question 14

What type of REACTION is it in AIR with Al ?

Answer 14

• Slow

Question 15

What type of REACTION is it in AIR with Si ?

Answer 15

• Slow

Question 16

COLOUR of P FLAME and what type of REACTION is it in AIR?

Answer 16

• Brilliant White

* SPONTANEOUSLY COMBUSTS 💨

Question 17

COLOUR of S FLAME and what type of REACTION is it in AIR?

Answer 17

• Blue as in Sea is Blue 🌊

* Burns Steadily

Question 18

Why does Al2O3 have a lower MP than expected?

Answer 18

bcos the 3+ ions DISTORT the OXYGEN’s electron cloud ☁️ to make the bonds partially covalent

Question 19

Which are the Simple Covalent OXIDES and what are their pH’s?

Answer 19

H3 PO4

H2SO3 and H2SO4

pH: 0-2

Question 20

Usually, S + O2 ➡️ SO2

BUT, what’s required to make SO3?

Answer 20

• HIGH temperature 🔥

* 🐱 CATALYST

Question 21

Define the term “Amphoteric” and gave an example

Answer 21

it can act as an acid OR base

Al203

Question 22

Silicon Dioxide is classed as _____ because it reacts with _____ to form _____

Answer 22

• ACIDIC
• BASES
• SALTS

Question 23

Sodium Oxide with HCL —> ?

Answer 23

2NaCL + H20

Question 24

Magnesium Oxide with Sulfuric Acid —> ?

Answer 24

MgSO4 + H20

Question 25

Aluminium Oxide with Sodium Hydroxide AND WATER —> ?

Answer 25

2NaAL(OH)4

Question 26

Aluminium Oxide with Sulfuric Acid —> ?

Answer 26

Al2(S04)3 + 3H20

Question 27

Silicon Dioxide with Sodium Hydroxide —> ?

Answer 27

Na2SiO3 + H20

Question 28

Phosphorus Oxide with Sodium Hydroxide

—> ?

Answer 28

4Na3PO4 + 6H20

Question 29

Sulfur Dioxide with Sodium Hydroxide —>

Answer 29

Na2SO3 + H20

Question 30

Sulfur Trioxide with Sodium Hydroxide —>

Answer 30

Na2SO4 + H20