Topic 6- Groups in periodic tables Flashcards
Why are there set groups in the periodic table?
-Some elements (abt every 8 in atomic ascending number)
-Have the same number of electrons on thier outer shell
-They have the same chemical properties
What is group 1
alkali metals
x2
Alkali metal properties
- Soft
- Relatively low melting/boiling point
Metal + water
—> Metal hydroxide + hyrdogen
Describe reaction of Litium + water…
-Rapidly moves across water
-Fizzes
-Produces colourless ssolution
sodium hydroxide + hydrogen
exothermic
Describe reaction of Sodium + water…
-Rapidly moves across
-Fizzes
-Melts into ball
lithium hydroxide + hydrogen
exothermic
Describe reaction of Potassium + water…
-Rapidly moves across water
-Fizzes
-Lilac flame
Potassium hydroxide + hydrogen
exothermic
Pattern between reaction of alkali metals with water
-Fizzes
-Rapid movement
-More vigerous going down list
Why does reactvity increase as atomic no. increases for group 1?
-Less attraction between posittive nucleus
-More distance
-Easier for electrons to transfer
Rubidium/ Caesium + water?
only need tto predict this
-Sinks
-Explodes
What is group 7
halogens
What are the colours of chlorine, bromine and
iodine a
-Pale Yellow
-Yellow/Green
-Red brown
darker as you go down
Pattern of group 7?
going down/ increaseing atomic no.
-Colour darkens
-INCREASE in boiling/melting point
-Less reactive
-Harder
-More denser
Describe the chemical test for chlorine…
blue litmus paper turns red
(for gas, dampen with water before holding it over gas)
then bleaches/whitens
Haligons react with metals to form…
-Metal Halides
-Ionic bonds
-Less reactive
