Particles Flashcards
Copper-63 is 69.2% abundant and Copper-65 is 30.8%. Calculate the relative atomic mass of copper to 1 d.p.
(69.2 * 63 + 30.8 * 65) / 69.2 + 30.8 = 6361.69 / 100 = 63.6169
63.6 (1 d.p.)
How do solids become a liquid?
Once the particles get enough energy (usually by being heated) they break free of their bonds and can move freely, becoming a liquid?
How do you calculate the atomic mass?
Number of protons + neutrons
how do you calculate the atomic number?
number of protons or electrons
How do you work out the relative atomic mass of an element?
sum of (isotope abundance*mass) / sum of abundance of all isotopes (usually 100)
How does a liquid become a gas?
The liquid particles gain energy(usually from heat) and vibrate faster, eventually they gain enough energy to break free of all their bonds completely and become a gas
How much bigger is the radius of the atom than the radius of the nucleus?
the radius of the nucleus is 10,000 times smaller than the radius of the nucleus
In liquids, the particles have ______ forces of attraction.
weak
Liquids have a _____ volume, but can change _____ to fit a container.
definite, shape
solids have a definite _____ and _____ because the particles are fixed in place
shape, volume
The particles have _____ forces of attraction in solids.
strong
Unlike solids, in a liquid the particles can _____
move
What 3 subatomic particles make up an atom?
Proton, Neutron and Electron
What are 3 issues with the particle model?
1) Does not show correct size of particles
2) Particles aren’t necassarily spheres
3) Doesn’t include intermolecular forces
What charge does an atom have?
No charge, and atom is neutral
What did Ernest Rutherford do and when?
he made the nuclear model in1909
What did J.J.Thomson do and when?
He made the plum pudding model in 1897
What did John Dalton say about atoms and when?
He said that they were solid spheres in the 1800s
What did Niels Bohr do and when?
He discovered elctron shells in 1913
What happens to an atom if it loses or gains electrons?
it becomes charged and an ion
What happens to the particles in a solid when it is heated up?
they gain energy and vibrate faster
What happens when a gas is heated up in a non-expandable container?
The pressure of the container increases
What happens when a gas is heated up in an expandable container?
The volume of the container expands
What is a negative ion called?
anion
What is a positive ion called?
Cation
What is avogadro’s constant?
6.02*10^23
What is different about isotopes of atoms?
they have the same number of protons and electrons but a different number of neutrons.
What is relative atomic mass?
The average mass of all othe isotopes of that element
What is the charge of electrons?
-1
What is the charge of Neutrons?
0
What is the charge of Protons?
+1
What is the difference between ions and atoms?
Ions have a charge
What is the law of conservation of mass?
in a chemical reaction, atoms cannot be created, destroyed or changed, but their arragements can change.
What is the melting point?
the melting point is a temperature (or range) in which solid particles break bonds and become liquid.
What is the relative mass of Electrons?
1/1836
What is the relative mass of Neutrons?
1
What is the relative mass of Protons?
1
What is the rough radius of an atom?
0.1 nm
What is the valence shell?
the outer shell on any atom.
What subatomic particle did Ernest Rutherford discover?
the Proton
What subatomic particle did James Chadwick discover?
the Neutron
What type of structure do solids form?
regular lattice structure
Which is the only electron shell that can be used in reactions?
The valence or outer shell.
Who discovered electron shells and when?
Niels Bohr in 1913
Who discovered protons?
Ernest Rutherford
Who discovered the neutron?
James Chadwick
Who had the earliest atomic theory ever recorded and when was it?
Democritus, 500 B.C.
Who made the nuclear model and when?
Ernest Ritherford in 1909
Who made the plum pudding model and when?
J.J.Thomson in 1897
Who said that atoms were solid spheres and when?
John Dalton in the 1800s
