Groups in the Periodic Table Flashcards
How are elements arranged in the periodic table?
Ordered by increasing atomic number
How many electrons are in the outer shell of a group 1 element?
One
Why do elements in the same group have similar chemical properties?
They have the same number of electrons in the outer shell
What group of the periodic table are the alkali metals?
Group 1
What are the properties of alkali metals?
Relatively low melting points and soft
Why are group 1 elements called the alkali metals?
They react with water to form alkaline solution
Why should alkali metals be stored in oil?
To prevent them reacting with water vapour and oxygen in the air
What would be observed when lithium reacts with water?
Slowest reaction of the alkali metals, bubbles of hydrogen are produced and doesn’t melt
What would be observed when sodium reacts with water?
Faster reaction than lithium, floats on the surface of water, bubbles of hydrogen are produced which cause the sodium to whizz around the surface of the water and melts as enough energy is given out to meet sodium’s melting point
What would be observed when potassium reacts with water?
More violent reaction than sodium, bubbles of hydrogen are produced which cause the potassium to whizz around the surface of the water, melts into a shiny ball and burns with a lilac flame
What is the order of reactivity of the first 3 alkali metals with water?
Lithium < Sodium < Potassium
What is the prediction of the reactivity with water trend down group 1?
Reactivity increases down group 1
Why does reactivity increase down group 1?
The number of electrons shells increases down the group so there is more electron shielding, there is weaker attraction between the positive nucleus and outer shell electrons, thus means it’s easier to remove an outer shell electron to form a positive metal ion
Which group 1 element would you expect to react most violently with water?
Reactivity increases down the group so francium will react most violently with water
What groups are halogens in?
Group 7 because they have 7 outer shell electrons
What is the colour and state of chlorine at room temperature?
Pale green gas
What is the colour and state of bromine at room temperature?
Red-brown liquid
What is the colour and state of iodine at room temperature?
Black solid