Basic inorganic Flashcards
Define atom
The smallest unit quantity of an element that may exist either alone or in chemical combination with another element.
What is the mass of a proton?
1.673 x 10^-27 kg
What is the mass of a neutron?
1.675 x 10^-27 kg
What is the mass of an electron?
9.109 x 10^-31 kg
What is the number of protons/electrons in an atom?
The atomic number, z.
What is the number of protons+neutrons in an atom called?
The mass number, A.
What are isotopes?
Forms of the same element that contain equal numbers of protons but different numbers of neutrons in their nuclei.
What is one atomic mass unit called?
A Dalton (Da)
What is the evidence for isotopes?
Mass spectrometry.
How can the emission spectrum of hydrogen be recorded?
By passing an electric discharge through hydrogen gas, splitting the molecules into atoms and exciting electrons. As the excited electrons return to ground state, they emit energy.
What is spectroscopy?
The study of how atoms emit/absorb electromagnetic radiation.
What is frequency and the units?
The number of wavelength crests passing a point per second, s^-1, Hz.
What is the symbol for frequency?
Nu, greek N.
What is the symbol for wavelength?
Lambda.
What is the velocity of light?
C, 2.998x10^8 ms^-1.
What is the equation for the velocity of a wave?
c=lambda x nu.
What is the equation for the energy of a photon?
E = h x nu
What is the photoelectric effect?
When UV light is fired at a metal plate, electrons are ejected. In order for an electron to be ejected, each individual photon needs enough energy.
What is the equation for the threshold energy of the electron?
E=hxnu
What is the work function?
The name given to the threshold energy of an electron (in a single atom)
What is the equation for the work function?
Work function = h x v - E(ke)
What is the evidence for the wave nature of light?
In the early 1900s, Young did an experiment passing light through two closely spaced slits. It was found that the screen behind had areas of light and dark as waves can interact constructively or destructively.
