ES 3 - Inorganic Chemistry and the Periodic Table Flashcards
What does chlorine look like under standard conditions?
Chlorine is a pale green gas under standard conditions
What does bromine look like under standard conditions?
Bromine is a red-brown liquid under standard conditions
What does iodine look like under standard conditions?
Iodine is a violet solid under standard conditions
Why does the reactivity of halogens decrease down the group?
As we move down group 7 the number of electron shells increase, this increases the shielding from the nucleus as well as the atomic radius. Both of these factors decrease the nuclear attraction of outer electrons, making it harder for the halogen to gain electrons
Why does the volatility of the halogens decrease down the group?
Halogens only have intermolecular instantaneous dipole-induced dipole forces between their molecules. As we move down the group the number of electrons in the halogen molecule increases, thus the instantaneous dipole-induced dipole forces between the molecules become stronger, taking more energy to break
Why are halogens more soluble in cyclohexane than water?
Halogen molecules are non-polar, so they do not dissolve very well in polar solvents like water, but they will dissolve readily in non-polar solvents like cyclohexane
What are the results of the halogens’ reactions with Ag+ ions?
Chlorine and Ag+ ==> White precipitate
Bromine and Ag+ ==> Cream precipitate
Iodine and Ag+ ==> Yellow precipitate
What are the solubilities of silver halide precipitates in ammonia?
Silver chloride: soluble in dilute ammonia
Silver bromide: soluble only in concentrated ammonia
Silver iodide: insoluble in dilute and concentrated ammonia
How do halogens react with halide ions?
Less reactive halide ions are displaces. Chloride will displace bromide and iodide ions, bromide will only displace iodide ions and iodide will not displace halide ions
How are hydrogen halides brepared?
X- + H3PO4 ==> HX + H2PO4-
Where X is a halogen
How does HBr react with H2SO4?
2HBr + H2SO4 ==> SO2 + Br2 + 2H2O
Why is HF a weaker acid than HCl?
The F- ion forms ionic bonds with the H3O+ ions in solution, which means there is an equilibrium between the bound and unbound forms of the acid
H3O+F- <==> H3O+ + F-
What are the uses of chlorine?
- Sterilisation of water
- Bleaching for use in the paper or textiles industry
What are some risks associated with the storage and transport of chlorine?
- Chlorine is extremely toxic and can cause irreversible lung damage and eye damage upon exposure
- Some chlorine compounds, such as those made when exposed to water, are carcinogenic
