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Chemistry Ch.3+4
Term | Definition |
---|---|
Most abundant element on Earth | Oxygen |
Most abundant element in the human body | Oxygen |
Democritus model | Called smallest possible particle of matter an element |
Aristole+Greeks | 5 elements (earth, water, fire, air, eather) |
Alchemists | Thought elements could be changed into different elements |
Law of constant composition | Given compound always has same proportion of elements |
Dalton’s atomic theory | Elements are made of tiny particles -all atoms of an element are identical -atoms of 1 element differ from those of others -atoms combine in specific ways -atoms are indivisible in chemical processes |
Thompson model | -positive and negative charges floating around -discovered electrons(cathode ray tube) -plum pudding model |
Marie Curiel | -2 Nobel prizes -coined term “radiation” -discovered 2 elements |
Bohr model | -atom is mostly empty space -electrons orbit |
James chadwick | Discovered neutron |
Electron | Negative(-1 charge) |
Neutron | Neutral(no charge) |
Proton | Positive(+1 charge) |
Atomic # | Number of protons(usually equal to # of electrons) |
Atomic mass | # of protons and neutrons |
Isotope | Same element w/ different # of neutrons |
Allotrope | Same element or isotope w/ different formation |
Dimitri Mendeleev | Designed first periodic table |
Mosely | Developed first modern periodic table |
Groups or families(on periodic table) | Columns(up and down) |
Periods(on periodic table) | Rows(sideways) |
Ion | Atom that has gained or lost electrons |
Positive ion | Atom that has lost electron(metals) |
Negative ion | Atom that has gained electron(non-metal) |
Oxidation # | Combining ability of an element |
Chemical bond | Force that holds atoms together in a compound |
Ionic bond | Electrons are transferred creating opposite charges that attract |
Chemical formula | Indicates the elements in a compound and the ratio of those elements |