periodic table and atomic structure
what is an element?
They are only made of one type of atom
what is a compound?
A compound consist of two or more elements that are chemically combined
what is a Mixture
A mixture consist of two or more elements or compounds that are not chemically combined
what are properties of alkaline metals?
They are soft and can be cut with a knife.
The softness increases going down the group.
They have a low density.
They have a low melting and boiling point.
They conduct electricity.
They are shiny when freshly cut
what are properties of transition metals?
They are hard and good conductors
They are unreactive
They are malleable and ductile
They have a high density in high melting point and boiling point
what are properties of noble gases?
They are colourless odourless and unreactive
what are properties of halogen?
They are very reactive and toxic or harmful because they are so Reactive
Halogen react with metal to form ionic compounds they gain one electron forming a positive Ion
what does the periodic Table, tell us
The group that an element is and tells us the number of electrons in the outer shell
The period that that element in tells us how many electrons shells that element has
The first shell could have maxed two electrons
The second shell can have max eight electrons
what is an ion?
An iron is a particle that has a charge they are electrically charged because they have an imbalance of protons and neutrons
what is an isotope?
An isotope is an element with the same number of protons but different number of neutrons isotopes have different physical properties but the same chemical properties
what did Newlands do?
Newlands followed the law of octaves. Some element elements in the same group didn't have the same properties ordered the elements by increasing atomic mass.
what did Mendel leave do?
Mendel leaf group the elements with similar properties left gaps so undiscovered elements could be fitted. He swapped some elements so they fit in the right group.