period 3

Question 1

sodium with h2o

Answer 1

2Na +2H2O—–> 2NaOH +H2. ph=13-14

Question 2

magnesium with H2O

Answer 2

Mg +2H2O(l) —–> Mg(OH)2 +H2 ph=9-10
Mg + H2O(g) ——> MgO +H2

Question 3

chlorine with H2O

Answer 3

Cl2 + H2O —–> HClO +HCl(no sunlight) ph=2-3
2Cl2 +2H2O —->4HCl + O2(sunlight)

Question 4

sodium with O2

Answer 4

2Na + 0.5O2 —-> Na2O
2Na+O2—–> Na2O2.
orange flame and white solid

Question 5

magnesium with O2

Answer 5

2Mg +O2—->2MgO
bright white flame and white solid

Question 6

aluminium with O2

Answer 6

4Al +3O2—–> 2Al2O3
has to be powder or strong oxide layer on Al inhibits reaction
bright white flame and white solid

Question 7

silicon with O2

Answer 7

Si +O2 —->SiO2
orange flame pure for of SiO2 is white solid

Question 8

phosphorus with O2

Answer 8

4P + 5O2—–> P4O10
white flame and white fumes

Question 9

sulfur with O2

Answer 9

S + O2—–>SO2
pale blue flame and colourless gas

Question 10

sodium oxide with h2o

Answer 10

Na2O +h2o—-> 2NaOH
ph=13-14

Question 11

magnesium oxide with h2o

Answer 11

MgO +H2O—–> Mg(OH)2
ph=9-10

Question 12

aluminium oxide and silicon oxide

Answer 12

both insoluble so no reaction

Question 13

phosphorous oxide with h2o

Answer 13

P4O10 +6H2O——>4H3PO4
ph=1-2

Question 14

sulfur dioxide with h2o

Answer 14

SO2 +H2O—–> H2SO3
ph=2-3

Question 15

sulfur trioxide with h2o

Answer 15

SO3 + H2O—–> H2SO4

Question 16

Na2O + H2SO4

Answer 16

Na2SO4 +H2O

Question 17

MgO + 2HCl

Answer 17

MgCl2 +H2O

Question 18

Al2O3 + 6HCl

Answer 18

2AlCl3 + 3H2O

Question 19

Al2O3 + 2NaOH +3H2O

Answer 19

2NaAl(OH)4

Question 20

H3PO4 +3NaOH

Answer 20

Na3PO4 +3H2O

Question 21

P4O10 +12NaOH

Answer 21

4Na3PO4 + 6H2O

Question 22

SO2 +2NaOH

Answer 22

Na2SO3 +H2O

Question 23

P4O10 +6Na2O

Answer 23

4Na3PO4

Question 24

P4O10 +6MgO

Answer 24

2Mg3(PO4)2