Chemistry Unit 1
Convert 1 angstrom into nanometers
1 angstrom = 0.1 nanometers
Dalton's atomic theory
1. All matter is made up of atoms 2. Atoms can neither be created nor destroyed 3. Atoms of the same element are identical 4. Compounds are formed through the combination of elements 5. Chemical reactions involve atoms recombining to form new substances
Bohr's quantized shell model rules
1. Electrons can only occupy certain energy levels 2. Electrons can exist in an energy level without losing energy 3. Electrons only absorb or emit energy when they change their energy levels
Why does the atomic radius increase as you move down a group?
1. the atom has more energy levels 2. the valence shell is shielded by more shells, therefore, the attraction that the nucleus (nuclear charge) has on the outer shell is weaker, causing it to be farther away from the nucleus
Problems with Rutherford's model
1. the electron would lose energy as it is orbiting the nucleus and eventually collapse into the nucleus 2. All elements create a unique, signature colour when excited
Why does the atomic radius decrease as you move from left to right in a period?
1. the nuclear charge increases while the number of energy levels do not. This allows the nucleus to have a stronger attraction on the outer shell, pulling it closer to the nucleus, which makes the atom smaller and more compact
elementary charge?
1.6 x 10e-19C (coulomb)
1 amu = ?g
1.66 x 10e-24
1 amu = ?kg
1.66 x 10e-27
When converting from left to right (larger unit to smaller unit), do you multiply by 10e+ or 10e-?
10e+
When converting from right to left (smaller unit to larger unit), do you multiply by 10e+ or 10e-?
10e-
What is the approximate diameter of an atom?
10e-10m
What is the approximate diameter of a nucleus?
10e-15m
How many cm is = to 1 in?
2.54cm = 1 in
How many grams is in 1 lb?
454 grams = 1 lb
Do cold gases produce an absorption spectrum or emission spectrum?
Absorption spectrum
Latin name of Silver
Agentium
What is a diatomic element?
An element whose natural state in a molecule of 2 atoms of the element
Latin name of Gold
Aurum Au
Group 2 elements
Beryllium Be Magnesium Mg Calcium Ca Strontium Sr Barium Ba Radium Ra
Group 13 elements
Boron B Aluminum Al Gallium Ga Indium In Thalium Tl
How were the elements arranged on the first periodic table?
By order of increasing atomic mass
Group 14 elements
Carbon C Silicon Si Germanium Ge Tin Sn Lead Pb
Latin name of Copper
Cuprum Cu
Who is considered the author of the modern periodic table?
Dmitri Mandeleev
Which elements are least electronegative?
Elements on the right side of the periodic table because they want to lose their electron(s), not gain any
Which elements are more electronegative?
Elements that "want" electrons; elements further to the right of the periodic table (except for the noble gases)
Do hot gases produce an absorption spectrum or emission spectrum?
Emission spectrum
Latin name of Iron
Ferrum Fe
How did Mandeleev choose group elements on the periodic table?
First: based on physical and chemical properties Second: based on increasing atomic mass
Group 17 elements
Fluorine F Chlorine Cl Bromine Br Iodine I Astatine St
Name the measurement units in order from largest to smallest
Gm Gigametre Mm Megametre Km Kilometre Hm Hectometre Dam Dekametre M Metre Dm Decimetre Cm Centimetre Mm Millimetre um Micrometre Nm Nanometre
What are the diatomic elements?
H Hydrogen O Oxygen Br Bromine F Fluorine I Iodine N Nitrogen Cl Chlorine
What did J.J. Thompson do?
He discovered electrons
What did chadwick do?
He discovered the neutron
What did Rutherford do?
He discovered the nucleus and the proton
Group 18 elements
Helium He Neon Ne Argon Ar Kripton Kr Xenon Xe Radon Rn
Who re-arranged the periodic table in order of increasing atomic number as opposed to increasing atomic mass?
Henry Mosely
What is the atomic mass?
How heavy the element is
Latin name of Mercury
Hydragyrum Hg
Alkaline earth metals
Ions are not soluble in water
Alkali metals
Ions are soluble in water
Who developed the first periodic table?
Julius Lothar MEYER
Latin name of Potassium
Kalium K
Group 1 elements
Lithium Li Sodium Na Potassium K Rubidium Rb Cesium Cs Francium Fr
Latin name of Sodium
Natrium Na
Group 15 elements
Nitrogen N Phosphorus P Arsenic As Antimony Sb Bismuth Bi
Are noble gases electronegative?
No, noble gases do not have electronegativities because they are stable
Group 16 elements
Oxygen O Sulfur S Selenium Se Tellurium Te Polonium Po
Latin name of Lead
Plumbum Pb
What did Democritus do?
Proposed the existence of atoms
Latin name of Tin
Stannum
Latin name of Antimony
Stibium Sb
What is electron affinity?
The amount of energy it takes to add an electron to a neutral atom, making it a -1 ion
What is ionization energy?
The amount of energy it takes to remove an electron from an atom; how tightly an element holds on to its electrons AKA how much energy it takes to make the neutral atom into a +1 ion
What is 1st ionization energy?
The amount of energy it takes to remove one electron from the atom, making it a +1 ion
What is 2nd ionization energy?
The amount of energy it takes to remove the second electron from the atom, making it a +2 ion
How does the atomic radius change within the period table?
The atomic radius increases as you move from the right of a period to the left. It also increases as you move down a group.
What was John Dalton's model
The billiard ball model
How does the electron affinity change within the periodic table?
The electron affinity increases as you move from right to left in the periodic table. It also increases as you move top to bottom in a group.
Which elements have the least ionization energy?
The elements to the left of the periodic table because they will become more stable by losing their valence electrons
Which elements have the highest ionization energy?
The elements to the right of the periodic table because they will become more stable from gaining valence electrons
How does the ionization energy change within the periodic table?
The ionization energy increases from left to right in a period. The ionization energy increases from bottom to top in a group.
What does the atomic number represent?
The number of protons
What was rutherford's model
The planetary model
What was J.J Thompson's model?
The plum pudding model
What is the atomic radius?
The radius of a neutral atom
What is the ionic radius?
The radius of an ion
What is electronegativity?
The tendency of an element to attract electrons
Electron affinity and electronegativity are practically the same.
True
Electron affinity is the opposite of ionization energy.
True
Nonmetals form covalent oxides.
True. They are acidic in aqueous solutions.
Metals form ionic oxides.
True. They are basic in aqueous solutions.
Some metals and metalloids form amphoteric oxides.
True. They can act as bases or acids in aqueous solutions.
What is the relation of mass/weight to volume and/or density?
W = V x D
Periodic Law
When elements are arranged according to increasing atomic number, properties of elements repeat in regular intervals
Latin name of Tungsten
Wolfram W
Do metalloids have properties of metals and non-metals?
Yes
Do non-metals have low boiling and melting points?
Yes
What does oxidize mean?
to lose electrons