Chapter 1 Flashcards
relative charge of a proton?
+
relative charge of a neutron?
0
relative charge of a electron?
-
relative mass of a proton?
1
relative mass of a neutron?
1
relative mass of an electron?
0
What is the charge of the nucleus?
positive
what fraction of the cell is the nucleus ?
1/10,000
what is the charge of an atom?
neutral
what is the plum-pudding model?
a ball of positive charge with electrons scattered randomly throughout, no empty space, no protons neutrons or nucleus, JJ Thompson.
What did Earnest Rutherford do?
He discovered the nucleus.
How did Rutherford discover the nucleus?
Rutherford fired positive particles at an atom, most went straight through meaning there was empty space, but some deflected as the positive charge of the nucleus repelled them like magnets and some bounced back showing there is a small, dense nucleus.
What did Bohr do?
Bohr discovered that electrons exist in shells
definition of an element
a substance made up of only one type of element.
definition of a compound
two or more different elements that are chemically combined
definition of a chemical reaction
when a new substance is made
what is filtration used for?
separating solids and liquids
what is crystalisation used for?
separating soluble solid from liquids
what is distillation used for?
separating solutions or multiple solids
what is chromotography used for?
separating different substances dissolved in a liquid
definition of an isotope
where the number of neutrons differs but the number of protons stays the same
what is the formula to find the average atomic mass of an isotope?
(mass of isotope 1 x percentage of atoms have that number of neutrons) + (mass of isotope 2 x percentage of atoms that have that number of neutrons) over 100
what is the atomic number?
the number of protons in an atom
what is the atomic mass number
the number of protons and neutrons in an atom
