Chemisty Test Flashcards
What is an isotope?
Atoms with the same number of protons and diffrent number if nutrons
What is an ion?
An ion is an atom that has lost or gained an electron to become fully charged
Daltons billard ball model was made in
1803
Thomas plumpudding model was made in …. and had….
1904 and had protons spread evenly with negative electrons embeaded trhougout
Rutherford model was made in … and had …
1911 and had a nuclus
Ruthfird - bohr model was made in … and had …
1913 and had shells
What did newland notice while making the periodic table
Noticed properties repeated every eight elements
How did newland order the table?
By weight and atomic mass
What mistake did newland make
Left no gaps for newly disscoverd elements
How did mendeleev order the periodic table
In order of atomic mass and groups based of properties
What did mendeleev do?
Leff gaps for elements he belived existed but hadnt discovered yet . Elements discovered fitted his pridictions
As you go down the group of the alkli metals the reactivity
Increases
Where are the alkli metals
Left hand side
What do the alkli metals inscrease in
Atomic radius, electron shells sheilding the outer electron, melting and boiling points and increase in ease of loosing outer electrons to form a postive ion
The first three alkli metals do what as water density increases
Float
What is group seven called
Halogens
