Chapter 12 Periodic table and trends Flashcards
What group and how many valence electrons do alkali metals have
Group 1 and 1 valence electron
Physical properties of alkali metals
Soft metals
Shiny
Low density
Low melting point
React violently with water and form basic hydroxide solutions
Physical trends in alkali metals
As you go down the group
Density increases
Melting point decreases
Chemical trends in alkali metals
As you go down the group
Reactivity increases
What are group 1 elements called
Alkali metals
What are group 7 elements called
Halogens
General properties of halogens
Form diatomic molecules
Are all poisonous
Physical trends of halogens
As you go down the group
Boiling point increases
Density increases
Colour becomes darker
What ion is formed when halogens react with metals
What is its charge
halide ions
Negative
Chemical trends of halogens
As you go down the group
Reactivity decreases
What happens when a halogen reacts with a halide solution
A halogen will displace a less reactive halogen from a solution of its halide
Metalloid
An element that has properties of both metals and non-metals
Transition metals
Elements in the middle of the periodic table
Physical properties of transition metals
High density
High melting and boiling points
Conduct heat and electricity
Hard and strong metals
Chemical properties of transition metals
No clear trend in reactivity
Form coloured compounds
Many transition elements and their compounds act like catalysts
Form ions with different charges
Can form more than one compound with one element
Have variable oxidation numbers
