1.1 Inside the atom Flashcards
What is the charge of a proton relative to a proton?
» + 1
What is the charge of an electron relative to a proton?
» - 1
What is the charge of a neutron relative to the proton?
» 0
What is a nucleon?
» Either we can use the word for a proton or a neutron
How does an uncharged atom become an ion?
» If it gains or loses electrons
What is an isotope?
» Same version of an element with the same number of protons but different number of neutrons
What is the Proton number equal to?
» Atomic number
What is the symbol for Atomic number?
» Z
What is the nucleon number?
» Total number of protons and neutrons inside the nucleus
What is the nucleon number equal to?
» Mass number of the atom
What is the symbol for nucleon number?
» A
What is a nuclide?
» Each type of nucleus
What is the specific charge of a particle?
» The specific charge of a particle is defined as the charge per unit mass, and its units are Ckg^−1
What is the formula for calculating the specific charge of a particle?
Charge of the particle / mass of the particle
What is the charge of a proton?
» + 1.60x10^-19
What is the charge of the neutron?
» 0
What is the charge of the electron?
» -1.60x10^-19
What is the mass of a proton relative to a proton?
» 1
What is the mass of a neutron relative to a proton?
1
What is the mass of an electron relative to a proton?
» 0.0005
What is the actual mass of a neutron and a proton?
» 1.67x10^-27
What is the actual mass of an electron?
» 9.11 x 10^-31
What is the specific charge of a nucleus of 1H1?
» Has a charge of 1.60 x 10^-19
» Mass of 1.67 x 10^-27
» Specific charge is therefore 1.76 x 10^11 CKg^-1
What is the specific charge of an ion of the magnesium isotope 24 Mg 12?
» Has a charge of 3.2 x 10^-19 - Since it has 2 electrons
» Mass of 3.98 x 10^-26 Kg
» Specific charge is therefore 8.04 x 10 ^6 CKg^-1
Which part of the atom has zero charge?
» Neutron
Which part of the atom has the largest specific charge?
» Electron
Which part of the atom, when removed, leaves a different isotope of the element?
» Neutron
What is the charge of a positron?
» +1
Why do a positron and an electron curve in the opposite direction in pair production?
» Carry opposite charges,so magnetic field forces them in opposite direction
How did carl Anderson deduce the photograph was from a positron rather than an electron traveling in the opposite direction
» Speed is greater where track was curved
» Straighter track is where particle met the plate
» Direction of the curve shows it is positive
How do you convert from MeV into Joules
» Times by 1.60 x 10^-13
Describe how the strong nuclear force between 2 nucleons varies with the separation of the nucleons
» At a short distance between the nucleons roughly about 3fm, the strong nuclear force begins to overcome the electrostatic repulsion
» At a shorter distance of less than 0.5fm, the strong nuclear force becomes a repulsive force
» At a range larger than 4fm> the strong nuclear force between the nucleons is 0
What is the nature of an alpha particle?
» Helium nucleus
What is the interaction responsible for beta-decay?
» Weak nuclear force
What is one difference between an exchange particle and a photon?
» Photon has a rest mass of 0, whereas exchange particles have non-zero rest mass
What will happen to a positron produced by an interaction?
» Positron will annihilate with an electron and its mass will be converted into energy, to produce 2 photons
