4.2 Structure of the Nuclear Atom Flashcards
(29 cards)
What are three kinds of Subatomic Particles?
electrons, protons, neutrons
Electrons?
are negatively charged subatomic particles.
Cathode?
negative charged subatomic particles
Anode?
Positively charged subatomic particles
what is the charge of the protons?
Positive charge +1
what is the charge of the electrons?
Negative charge -1
what is the charge of the neutrons?
zero n^0
What is the mass of the protons?
1
What is the mass of the electrons?
1/1840 almost 0
What is the mass of the neutrons?
1
What is the location of the protons and neutrons?
inside the nucleus
What is the location of the electrons?
outside the nucleus (energy levels)
How did they discover subatomic particles?
First, thomson discovered electrons by cathode ray tube experiment.
What is the structure of the cathode ray tube?
Its a glass tube filled with gas at low pressure then he put 2 pieces of metal and connected them to a battery.
How did the cathode ray tube work?
A cathode ray (ray of electrons) its a glowing beam that passed between two metal plates, with one plate positively charged and the other negatively charged. Thomson observed that the cathode ray was strongly attracted to the positive plate, indicating the particles carried a negative charge. From this, he concluded that there must be something lighter than atoms—tiny, negatively charged particles moving at high speeds (fast moving particles and lighter than the atom), which he named corpuscles then electrons.
After thomson came ………… who determined the————–
Milikan, charge and mass of electrons using positive and negative plates through different directions and he found a ray attracted to the positive plate which indicate that electrons are negatively charged.
Thomson discovered the ——–
Milikan discovered the——-
1.)electrons
2.)Charge (+/-) and mass of the electrons
Goldstein discovered the ———
Protons (+ve charged particles)
Goldstein and Thomson made the———
plum-pudding model (blue berry muffin) where the dough is +ve (protons) and the blueberries are electrons stuck in the protons (no space between them)
Rutherford then discovered the——-
nuclear atomic model (that an atom has a nucleus which is a dense positive area)
Rutherford discovered the nucleus or (nuclear atomic model) through?
The Gold foil experiment
What was the gold foil experiment made up of?
A fluorescent screen , gold foil, and a source of alpha rays (+ve)
What did Rutherford conclude from the Gold foil experiment?
1.) Alpha rays passed through the atom so most of the atom is empty space
2.)Some rays are reflected back so they hit something dense and very small inside which is the nucleus
3.)Some rays are deflected (change direction) because of repulsion (positive rays hit the +ve nucleus) so the nucleus is positive
The plum-pudding model by Thomson and Goldstein stated that there is a nucleus. (true or false?)
False, the nuclear atomic model by Ruther ford is the one that stated that there is a nucleus that is dense a tiny compared to the electrons which occupy most of the volume.
