midterm exam 3 Flashcards
what is the trend for high ionization energy on the periodic table?
going up and right
what is the trend on the periodic table for larger atomic radius?
left and down
metals that like to lose one or more electrons to form _ ?
cations
these ions are said to be _ with noble gases?
isoelectronic
nonmetals like to gain one or more electrons to form _ and the chemical process of loosing electrons is called _ ?
anions, oxidation
reactions between nonmetal and _ tend to form compounds that are covalent where electrons are being _ between two atoms.
nonmetal, shared
chemical bonding between a metal and a nonmetal produces _ bond.
ionic
compounds and elements always have an overall electronic charge of _ .
zero
what are the elements involved in making chemical bonds and electronegativity ?
F,O,N,Cl,Br,I,S,C,H
<————————
( electronegativity)
substances can be either?
organic and inorganic
how is a substance identified as organic? what are the rules of play?
- CH
- C ( always 4 bonds) (most stable), N ( 3 bonds), O ( 2 bonds), F( 1 bond), H ( hydrogen bond)
- line angle structures may be drawn for convenience
how is a substance classified as inorganic? what are rules of play
- does not start with CH
- always count valence electrons first
- if the substance is an acid containing oxygen, the hydrogen is attached to the oxygen atom
-octet rule is king, share neighboring electrons - formal charge calculations: FC= group # - touch ( . -)
- minimize FC between atoms
- most electronegative atoms prefers (-) FC
- most electropositive atoms prefers (+) FC
what are the groups in the periodic table? what are the periods in the periodic table?
- groups: there horizontal rows of the elements
- periods: the vertical rows of the elements
what determines valance electrons in the periodic table?
- group
- example: group 4 elements have 4 valance electrons
what is a covalent bond?
when atoms share electrons
how to determine if a bond is polar or nonpolar?
- polar bond: electrons are unequally shared between atoms
- nonpolar bonds: electrons are shared equally between atoms
- difference is due to different electronegativities
what is the formula for dilution?
M1V1=M2V2
what is the equation for mass %?
mass %= mass solute/mass solution x 100%
what is the equation for molarity (M), or concentration?
molarity (M)= moles solute/liters solution
molarity (M)= moles solute/kg solvent
what is the formula for solution dilution?
M1V1=M2V2
what is the constant for speed of light?
3.0 × 10^8 m/s
(186,000 mi/s)
what is wavelength for violet and red light?
what is 1 nm equal to?
- red light, with a wavelength of 750 nm (nanometers), has the longest wavelength of visible light
- violet light, with a wavelength of 400 nm, has the shortest wavelength of visible light
- 1 nm = 1 × 10^ –9 m
what is frequency? what does a high frequency mean on a wavelength?
Frequency: The frequency of light, ν (nu,
pronounced “noo”), is defined as the number of cycles or crests that pass through a stationary point in one second
higher frequency=shorter wavelength
closers waves= more energy
what is a photon? what color has more photons?
- photon: particle of light
- violet light (shorter wavelength) carries more energy per photon than red light (longer wavelength)
what has the shortest wavelength and highest energy?
gamma rays
can damage biological molecules such as DNA
what are the waves on the electromagnetic spectrum from highest energy to lowest?
gamma rays -> x rays -> ultraviolet ( UV light) -> visible light ( ROYGBIV) -> infrared light-> visible & infrared radiations -> mircowaves
what types of rays are used to ionize biological molecules to kill cancer cells?
- gamma and x rays
- stops the cell division or completely kills the cancer cell, normal cells can sustain rays but side effects such as fatigue, skin lesions & hair loss
- try to minimize dosages
what is a white light spectrum?
a spectrum that has super small gaps but appears continuous
what is a hydrogen light spectrum?
mainly black spectrum with three-four thin colored lines ( orange blue, violet/purple)
what is a helium light spectrum ?
mainly black spectrum with 6-8 thin colored lines ( ROYGBIV)
what is a neon light spectrum?
black spectrum with all ROYGBIV with clusters of lines
energy of each Bohr orbit, specified by a ?
- quantum number ( n)
- n= 1,2,3,4,5,6
- are like steps on a number each with their own specified energy
- impossible for electrons to exist between orbits
what happens to a hydrogen atom when its excited and relaxed?
- higher energy orbit
- lower energy orbit
what are the quantum numbers for red (657 nm), blue-green ( 486 nm), violet (434) ?
- red: n= 1,2
- blue-green: 3,4
- violet= 4,5
what did the Bohr model fail to predict?
it failed to predict the emission
spectra of other elements that contained more
than one electron
the lowest-energy orbital in the quantum-
mechanical model is called the ?
1s orbit
what does the letter ( 1s) indicate ?
- subshell of the orbital and specifies its shape
- the possible letters are s, p, d, and f, each
with a different shape - orbitals within the s subshell have a spherical shape
what are shell values? number of shells and their respective letters?
- shell: n=1, n=2, n=3, n=4,
- number of shells: 1,2,3,4
- n=1 ( s), n=2 ( s, p) , n=3 ( s, p, d), n=4 ( s, p, d, f)
what is orbital and number of electrons in 1s1?
- orbital: 1s
- 1: number of electrons in orbital
what is Pauli exclusion principal?
orbitals may hold no more than two electrons
with opposing spins