Group 7 Flashcards
What are the appearance of gaseous halogens
Vary in appearance flourine is yellow and gas chlorine is pale green bromine is red brown liquid and iodine is solid
Why does electronegativity increase going down a group
As the atom get larger although the nuclear charge increase the atomic size also increase so the nucleas is further from the nucleas as well as more shielding these factors are more important than increasing the nuclear charge
Why does melting point increase going down the group
Larger atoms have more electrons so more can see waals forces between molecules stronger the lower the melting point the more volatile the element
What is oxidising power
The power of ability to gain an electron to form a negative ion
How does oxidising power change going down a group
Decreases as the nucleas is further away from outer electron and more shielding so less attraction to gain an electron
Why does atomic radio increase in ions compared to atom
The addition of the electron causes repulsion which increases the size
What happens to hydrogen halides going down the group
The melting point increases as bigger molecules so more electrons greater vow forces so need more energy to overcome except for hydrogen fluoride as there is hydrogen bonding
What happens to the bond strength going down the group in hydrogen halide
It decreases as the nucleas is further away form the share pair of electrons so less energy is required to break bond
Difference between halogen and Haida
Halogen is an atom an can be reduced to form an ion
Halide ion can be oxidised nd increases going down the group
What is the use of chlorine
Water purification
Bleach
Solvents
Polymers
What is an disproportional reaction
When an element is both reduced and oxidised in the same reaction
