halides group 2 and redox

Question 1

ca+O

Answer 1

CaO

Question 2

Ca+H2O

Answer 2

Ca(OH)2+h2

Question 3

metal + acid

Answer 3

salt + hydrogen

Question 4

why does ionisation energy decrease down group 2

Answer 4

atomic radius increases and more shielding so less attraction between nucleus and outer electrons

Question 5

CaO+H2O

Answer 5

Ca(OH)2

Question 6

solubility down group 2

Answer 6

increases

Question 7

ph of solution down group 2

Answer 7

increases, more alkaline

Question 8

group 2 agriculture

Answer 8

calcium hydroxide Ca(OH)2 is added to fields as lime by farmers to increase ph of acidic soils

Question 9

boiling point down group 7

Answer 9

bp increases as there are more electrons,stronger London forces, more energy required to break intermolecular forces

Question 10

fluorine

Answer 10

pale yellow gas

Question 11

chlorine

Answer 11

pale green gas

Question 12

bromine

Answer 12

red/brown liquid

Question 13

iodine

Answer 13

shiny grey solid

Question 14

astatine

Answer 14

black solid
solid sample has never been seen

Question 15

halogen halide displacement reaction

Answer 15

add solution if each halogen to aqueous solution of other halides.
to tell them apart add non polar solvent like cyclohexane

Question 16

coolers of cl,br and I

Answer 16

cl-pale green
br-orange
I-violet

Question 17

reactivity down group 7

Answer 17

reactivity decreases as atomic radius increases, more shielding, less nuclear attraction to capture electron from a mother species

Question 18

disproportionation reaction

Answer 18

a reaction in which the same element is both oxidised and reduced

Question 19

2 examples of disproportionation reaction

Answer 19

chlorine with water and chlorine with dilute sodium hydroxide

Question 20

Cl2+h2O

Answer 20

HClO+HCl

Question 21

cl2+NaOH

Answer 21

NaClO+NaCl+H2O

Question 22

NaClO is used as

Answer 22

bleach