C2 mindmap
- Created by: lilycarrterr
- Created on: 13-08-19 10:55
View mindmap
- C2
- development of the periodic table
- the periodic table was formed as chemists classified elements
- named the periodic table because of the regularly repeating patterns in the properties of all the elements
- mendeleev's periodic table had gaps for unknown elements
- named the periodic table because of the regularly repeating patterns in the properties of all the elements
- the periodic table was formed as chemists classified elements
- electronic structures and periodic table
- atomic number (proton) determines position
- no. of electrons in outer shell determines chemical properties.
- number of electrons in OS equals group number
- atoms of metals tend to lose electrons whereas those of non metals gain
- (and reactivity)
- number of electrons in OS equals group number
- no. of electrons in outer shell determines chemical properties.
- atomic number (proton) determines position
- group 1 - the alkali metals
- melting and boiling points decrease going down the group
- all react with water to produce hydrogen and an alkaline solution containing the metal hydroxide
- form positive ions charge +1 in reactions to make ionic compounds
- reactivity increases going down group
- all react with water to produce hydrogen and an alkaline solution containing the metal hydroxide
- melting and boiling points decrease going down the group
- group 7 - the halogens
- all form ions with a single negative charge in their ionic compounds
- form covalent compounds by sharing electrons with other non-metals
- more reactive halogens can displace a less reactive halogen from solution of one of its salts
- reactivity of the halogens decrease going down the group
- all form ions with a single negative charge in their ionic compounds
- explaining trends
- you can explain trends in reactivity as you go down a group in terms of attractuons between outer shell electrons and nucleus
- this depends on:
- distance between electrons and nucleus
- no. of occupied inner shells
- size of + charge on nucleus
- no. of occupied inner shells
- these factors must be taken into account in deciding how easy it is for atoms to gain/lose electrons.
- the increased nuclear charge, due to extra protons, going down a group is outweighed by the 2 other factors
- therefore electrons are easier for larger atoms to lose and harder to gain going down a group
- the increased nuclear charge, due to extra protons, going down a group is outweighed by the 2 other factors
- distance between electrons and nucleus
- this depends on:
- you can explain trends in reactivity as you go down a group in terms of attractuons between outer shell electrons and nucleus
- the transition elements
- compared with alkali metals, transition elements have higher melting &boiling points.
- stronger, harder & less reactive
- do not react vigorously with oxygen or water
- transition element can form ions with different charges
- inportant industrial catalysts
- compared with alkali metals, transition elements have higher melting &boiling points.
- development of the periodic table
Comments
No comments have yet been made