Big Idea #1
Ionization Energy
The amount of energy required to remove electrons from an atom
As an electron get closer to the nucleus the ______ to the nucleus gets ______
attraction, stronger
Effective nuclear charge
the pulling force that a valance electron actually feels; net positive charge(protons-non valence electrons)
Tin(ii) oxide is 88.10% tin and 11.90% oxygen. If 20g of this material was analyzed, what masses of tin and oxygen must be present to establish if the substance is pure?
17.62g Sn, 2.38g O
The maximum number of electrons that can occupy the third principle energy level is
18
According to quantum mechanic models, the element Neon would have a principle quantum number of
2
What is the maximum number of electrons that can occupy one orbital?
2
Speed of light(c)
3x10^8
The configuration of the outermost energy level in calcium is
4s^2
Iron(iii) Chloride is 34.43% iron with the rest being chlorine. How many grams of Chlorine would be present in a pure 150g sample of Iron(iii) Chloride?
98.4g Cl
Law of Multiple Proportions Compound A-1.750 g Compound B-.8750g Compound C-.4375 g
A/B=2 B/C=2 A/C=4
Law of Definite Proportions
Compounds have an unchanging chemical formula; Proust
Compounds
Constant composition, can be broken down by chemical means, not physical means
Density
Density=Mass/Volume
Oil Drop
Determined the charge on an electron
What happens to the effective nuclear charge of atoms as you move from left to right on the periodic table?
It increases
This person is given credit for discovering the electron was
JJ Thompson
Temperature Conversions
Kelvin=Celcius+273 Fahrenheit=Celcius x 1.8 +32
Dalton's atomic theory explained the observation that the percentage by mass of the elements is always the same, thus Dalton's atomic theory supports what law?
Law of definite composition
Molarity Equation
M1V1=M2V2
Law of Conservation of Mass
Mass is neither created nor destroyed; Lavoisier
Photoelectron Spectroscopy
Measures the ionization energy of all electrons in an atom
What happens to white light when it passes through a prism?
It breaks into its characteristic colors
Which element contains 7 electrons in its fourth energy level? (a)Br (b)Co (c)Ne (d)Se
(a)
Which element contains a full second energy level? (a)Ne (b)Ar (c)Be (d)He
(a)
Which element contains electrons with the highest energy? (a)Mg (b)Sc (c)O (d)K
(b)
Which of these orbital designations are invalid? (a)4s (b)3f (c)2d (d)3d
(b) or (c)
Laughing gas is a compound formed from Nitrogen and Oxygen in which there are 1.75g of N to 1g or O Below are given the compositions of several Nitrogen and Oxygen compounds. Which of these is laughing gas? (a)6.35g N,7.26g O (b)4.63g N, 10.58g O (c)8.84g N, 5.05g O (d)9.62g N, 16.5g O
(c)
Among the following groups of atoms, which have the same outer energy level configurations? (a)H,He (b)Li,Be,N,Ne (c)Mg,Al,Ca,Ga (d)N,PmAs,Bi
(d)
Dalton's Atomic Theory
1. All matter is made of atoms, which are indivisible and indestructible 2.All atoms of a given element are identical in mass and properties 3.Compounds are formed by a combination of two or more different kinds of atoms. 4.A chemical reaction is the combination, separation, or rearrangement of atoms; atoms are neither created nor destroyed in the course of an ordinary chemical reaction.
Radioactivity
1. Gamma(Y) Rays-high energy light 2.Beta Particles-high speed electrons 3.Alpha Particles-nuclear particle with a +2 charge
Rutherfords Metal Foil Expriment
1. Most alpha particles pass straight through thin metal foil 2. Some particles were greatly deflected -supported concept of small central positive nucleus
Two modifications to Dalton's Theory
1. Subatomic particles were discovered 2. Isotopes were discovered
Coulomb's Law
F=k(Q1Q2)/(d2) increase the distance, force decreases(inverse relationship)
Matter
Anything that occupies space and has mass
Avogadro's Law(Hypothesis)
At the same temperature and pressure, equal volumes of different gases contain the same number of particles
Atomic radius periodic trend
Atomic size increases down a column and decreases front left to right across a period. As you go down a column the number of electrons increases but more shells are added so the shielding effect increases. (effective nuclear charge increases) As you move from left to right across a period the number of electrons increases but they are less shells being added and so the nucleus pulls the electrons closer to itself.
Isotopes
Atoms of the same element with different numbers of Neutrons
Which pair of substances could be used to illustrate the law of multiple proportions? (a)SO2,H2SO4 (b)CO,CO2 (c)H2O,O2 (d)CH4,C6H12O6 (e)NaCl,KCl
CO,CO2
Elements
Cannot be decomposed into simpler substances by physical or chemical means
c=(wavelength)(velocity)
E=hv
If more protons in the nucleus pull electrons in tighter, then why don't atoms get smaller when going down a column?
Effective nuclear charge is constant, but shielding increases which causes electrons to stay further away from the nucleus and radius increases
Electronegativity Periodic Trend
Electronegativity increases from left to right across a period and decreases down a column. It increases from left to right because if the valence shell of an atom is less than half full then it requires more energy to lose an electron than to gain one and if the shell is more than half full then it is easier to gain an electron. As you move down a column there is more distance between the nucleus and the valence electrons, the there is less attraction to gain new electrons.
Explain the attractive forces between electrons and protons and how they affect energy from electron transitions
Electrons go to lower energy levels as they are attracted to the nucleus. to drop in energy levels the electron loses energy, and the larger the move the more energy is involved
The region around the nucleus where the electron is likely to be moving according to Bohr
Energy Levels
Precision
Getting the same value or close to the same value repeatedly
Notable Groups
Group 1: Alkali Metals Group 2: Alkaline Earth Metals Group 3-12: Transition Metals Group 17: Halogens Group 18: Noble Gases
Accuracy
How close a given measurement is to the accepted value
When electrons occupy orbitals of equal energy, on electron enters each orbital until all the orbitals contain on electron with parallel spins
Hund's Rule
Explain why a single atom of Hydrogen cannot produce all for Hydrogen spectral lines simultaneously
Hydrogen only has one electron so one Hydrogen atom can only produce one spectral line
Ionization Energy Periodic Trend
Ionization energy increases from left to right across a period and decreases down a column. Ionization energy increases from left to right because the atom's shells are almost full and atomize radius had decreased so there is more pull from the nucleus to keep the electrons. Ionization energy decreases down a column because the atomic radius increases so there is less pull from the nucleus to keep the electrons and because there is more shielding than further up the column.
Is effective nuclear charge a factor in how periodic properties within a column of the periodic table?
No, because the effective nuclear charge stays the same within a column, since they all have the same number of valence electron. The distance between the valence electrons and the nucleus would influence the attractive forces.
Does a gas discharge tube filled with boron emit the same wavelengths of light as a tube filled with Hydrogen?
No, each element produces different wavelengths of colors(different shades)
Do all colors of light have the same energy?
No, violets have the highest(shortest wavelength) and reds have the lowest(longest wavelength)
In order to occupy the same orbital, two electrons must have
Opposite spin
h
Plank's constant-6.26x10^-34 JS
What type of energy is gravity?
Potential
The amount of energy required to move an electron from one energy level to the next higher one is referred to as
Quantum
Mass Spectrometry
Relative abundance and masses of isotopes
What does the number of peaks in a PES spectrum reveal about the energy sub levels occupied by electrons in an atom?
The number of peaks equals the number of sub levels
Electronegativity
The tendency of an atom to attract electrons
The fourth principle energy level has ___ orbitals
Thirty Two
Law of Multiple Proportions
Two elements can come together in more than one way, forming compounds with similar though not identical formulas(whole number ratios); John Dalton
JJ Thompson
When high voltage was applied to an evacuated tide, a cathode ray was produced
Do all colors of light travel at the same speed?
Yes
Chemical change
a substance combines to form a new substance, changes color, forms a precipitate, bubbles produced, cannot be reversed
What happens to the effective nuclear charge of atoms as you move from top to bottom of a column on the periodic table?
effective nuclear charge stays the same
As wavelength increases
energy decreases
Stable electron configurations are likely to contain
filled energy sublevels
For An electron to move from an energy level close to the nucleus to an energy level far from the nucleus it would need to _______ energy
gain
Long wavelength
low frequency
Percent by mass formula
mass% =g solute/g solution
Nuclear charge
number of protons
Physical change
properties never change, goes from one physical state to another
Why are the color labels listed as plural?
the different wavelengths create different shades of the colors
