Chapter 3 Atomic Structure Flashcards
Explain the plum pudding model.
negatively charged electrons (raisins or blueberries) are surrounded by a positively charged “pudding”
What is the mass and charge of the proton, neutron and electron?
The relative mass of the proton and neutron is 1 while the electron is 1/1835 (negligible)
The charge of the proton is +1, neutron 0, electron -1
What does the Group number represent?
The amount of electrons in the outer shells
What does the period number represent?
The amount of occupied shells
What is all matter made up from?
small particles called atoms
What is the center of the atom called and which sub-atomic particles are found there.
The center is called the nucleus and protons and neutrons can be found there
What is the gold foil experiment and what did it prove.
the gold foil experiment was done by firing small positive particles at a thin gold foil. Most of the particles passed straight through with a few being deflected and a small number bouncing back.
Rutherford explained this by suggested that atoms are mostly empty space with a small positive central nucleus that contains most of the mass.
What is the mass number?
the total amount of protons and neutrons
What are Isotopes?
Atoms of the same element which have the same number of
protons but different number of neutrons
Why is relative atomic mass used instead of just the mass number?
We cannot include the mass number in the periodic table because,
for different isotopes, the mass number is different because of the
different number of neutrons in the nucleus.So, we use relative
atomic mass instead
How is the mass of atom measure?
Atoms have a very small mass, so we measure their masses relative to an atom of carbon -12
What is the formula for calculating the Relative atomic mass of an element?
100
