Group 7 Flashcards Preview

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Flashcards in Group 7 Deck (16):
1

Describe colour and density moving down group 7

Darker and denser

2

Why does electronegativity decrease down group 7

Bonding pair becomes further from the nucleus
Greater shielding

3

Why does boiling point increase down the group 7

Greater van deer walls

4

How do halogens react

By gaining an electron
Reduced

5

Up the group 7 the ability to ________ increases

Oxidise

6

More reactive halogens can______ less reactive Ines in metal halides

Displace

7

How do the reactions of halide atoms differ from halogens

Halide ions act as reducing agents
Reducing ability increases down the group

8

Why isn't the reaction of chlorine with sulphuric acid redox

Chlorine is not a strong enough reducing agent

9

What are the products of sodium halides with sulphuric acid

Fluorine- hydrogen fluoride
Chloride- hydrogen chloride
Bromide - hydrogen bromide + sulphur dioxide
Iodide - hydrogen iodide + hydrogen sulphate sulphur dioxide, solid sulphur

10

What is produced when a halide other than fluoride reacts with silver nitrate

Insoluble silver halide

11

Why is nitric acid added to a halide solution when testing for ions

Remove soluable carbinate which will form silver carbinate which is indistinguishable from the white precipitates formed

12

Give the results of the silver nitrate test

Silver Fluoride no ptt
Silver Chloridewhite ppt dissolves in dilute ammonia
Silver Bromide cream ppt dissolves in conc ammonia
Silver iodide yellow ppt doesn't dissolve

13

Show with oxidation states the reaction of chlorine with water when NOT in sunlight.State the name of this type of reaction

0. +1. -1
Cl2+H2O HClO+HCL
Disproportionation

14

Give the reaction of chlorine with water in sunlight

2Cl2+ 2H2O-----> 4HCl + O2
Means that chlorine must be added

15

Why must swimming pools be slightly acidic

HClO oxidises bacteria
This is removed as ClO- ions in alkaline

16

How are swimming pools kept slightly acidic

NaCl0+H2O Na+ + OH- + HClO