what is an atom
- the smallest part of an element
- invisible, but broken down into many different subatomic particles
- made up of protons, neutron and electrons
What is an isoptope?
Same number of protons; different number of neutrons
what is the electromagnetic spectrum
electromagnetic waves can travel through space + depending on wavelength, through matter.
Formula for wavelength speed
c= y x v
v= frequency y= wavelength c= velocity of travel (speed)
what is the emission spectra ( EXICTED STATE TO GROUND STATE; GIVING OUT ENERGY)
Line Spectrum: when energy is supplied to individual elements they emit a spectrum which only contains emissions at particular wavelengths. Each element has its own characteristic spectrum, known as a line spectrum (not continuous)
- each element emits specific wavelengths
- each wavelength corresponds to a discrete amount of energy
How does the emission spectra work?
- can be used to identify particular elements, as each element has its own, unique emission spectra
- energy supplied to electrons= electrons become energy and becoming EXCITED (move from ground state to excited state)
- When electrons drop from a higher level to a lower level they emit energy
- energy corresponds to a particular wavelength and shows up as a line in the spectrum
- when electrons return to ground state, the lines occur in the ultraviolet region
Electronic Configuration
electorns found in orbitals, each orbital can contain a maximum of 2 electrons each with opposite spins
THE AUFBAU principle:
The orbitals with the lowest energy are filled first
each orbital can contain a maximum of two electrons
HUNDS RULE: orbitals within the same subshell are filled singly first
Exeptions to aufbau prinicple
CHROMIUM: [Ar] 4s1 3d5
COPPER: [Ar] 4s1 3d10
IRON: [Ar] 3d6
SHAPES OF ORIBTALS
S» SPHERICAL
P» DUNG BELLS, 3 TYPES: PX (cross) PY AND PZ(sideways) (vertical)
emmision spectra for:
- hot object
- hot gas
HOT OBJECT: continous spectra (all the frequencies of light)
Hot Gas: certain little lines (certain frequencies OF LIGHT)
discontinous spectra
what is the absorbtion spectra
-absorbtion of energy
-from ground state to excited state
emmision +aborbtion =complete spectra
what is BOHRS explanation of the hydrogen spectra
- positive proton in nucleus
- electrons moving around it
- each orbit has a definitive energy associated with Citi
what is the ground state
electrons in their lowest energy level; with energy it can move to its excited state (other levels)
what are chemical properties of an element determined by
the electronic configuration
how can a scientists determine that electrons have distinct levels through which they travel from their ground-> excited state
emission spectra consist of discrete lines representing transients between the levels; if electors could be anywhere he spectra would be continuous; the convergence of lines in the spectra show that successive levels get closer in energy
