Ch 7 Preodicitey

Question 1

Bonding and structure

1) NA
2) MG
3) AL
4) SI
5) P
6) S
7) CL

Answer 1

1) giant metallic. Na
2) giant Metallica. Mg
3) giant metallic. Al
4) giant molecular (covalant). Si
5) simple molecular (covalant). P
6) simple molecular (covalant). S
7) simple molecular (covalant) Cl

Question 2

Bonding in SiO2

Answer 2

Covalant

Giant covalant

Question 3

Oxides and oxidation no of period 3

Answer 3

Na +.        Na2O
Mg +2.      MgO
Al +3.         Al2O3
Si +4.         SiO2
P +5.         P4O10
S +6 or +4.     So3
Cl +7.          Cl2O7

Question 4

Non metal chlorides period 3 reactions produce what

Answer 4

They are hydrolysed in h2o and release white funes of Hcl in a rapid reaction
PCl5 + 4H20 = H3PO4 + 5HCl
SiCl4 +2 H2O = SiO2O + 4HCl

Question 5

Flame tes for sodium ; magnesium: phosphorus

Heated with oxygen

Answer 5

Sodium     =  yellow flame 
Magnesium     = bright white
Phosphorous.   = Yellow or white

Question 6

1) Magnesium plus cold water

2) Hot magnesium plus water

Answer 6

1) Mg + 2 H2O = Mg(OH)2 + H2

2) Mg + H2O = MgO + H2

Question 7

Alminium oxide reaction with acid( H2SO4) and hot concentrated alkali (NaOH)

Answer 7

Al2O3 + 3 H2SO4. = Al2(SO4)3 + 3 H2O

Al2O3 + 2NaOH + 3H20. = 2NaAl(OH)4

Question 8

Reaction of SiO2 with hot concentrated Alkali (NaOH)

No reaction with acid

Answer 8

SiO2 + 2 NaOH. =. Na2SIO3 + H2O

Question 9

Phosphorous and sulfur oxide +. Water

Answer 9

P4O10 + 6H2O = 4 H3PO4

SO2 +H20 = H2SO4

Question 10

Phosphorous and sulfur oxide +. Water

Answer 10

P4O10 + 6H2O = 4 H3PO4

SO2 +H20 = H2SO4