Lecture 2 Flashcards
Chemistry is the study of
Matter and changes it undergoes
Physics is the study of
Motion, matter and energy interactions
Inorganic compounds contain all elements except
Carbon
Ionic and molecular compounds
Organic compounds contain
Carbon
Analytic chemistry studies
The percent composition of a sample
Atoms
Basic building blocks of matter
Smallest particle of an element
Composed of protons, neutrons, and electrons
An element is defined by its number of
Protons
Protons have a mass of
1 amu= 1.66 c 10^-27
Ions are
Atoms that have gain or lost electrons from their natural composition
Positive (cation) negative (anion)
O2 is is both
Molecule and element
Chemical properties are
Characteristics that describe the chemical reactivity of a substance. Result in formation of different compounds
Physical properties are
Do not describe the chemical reactivity of substance. A substance can display physical properties without a change in composition
Atomic number (Z) of an element is
The number of protons in the nucleus
The mass number (A) of an atom is
The sun of the proton (or atomic number) and the neutron number (N)
Atomic mass or atomic weight is the
Average mass of an atom in a natural sample of the element
Atomic number is equal to
The number of protons ( atomic number of carbon is 6)
Tells number of electrons
Mass number of an element is equal
To the number of protons plus number of neutrons
Electrons are ignored because they are weightless
Atomic weight is the average
Of the mass numbers of all isotopes of an element
Isotope are
Atoms with the same atomic numbers but with different atomic weights. Same number of protons (and electrons) but a diff is not be number of neutrons
Radioisotopes are
Heavier, unstable isotopes of an element that spontaneously decompose into more stable forms
- half live
Half live is
Time required to lose 1/2 of radioactivity
Carbon dating
Determines age of fossils by using half life
Who discovered isotopes
JJ Thompson
At 22 amu
Isotopes have the same atomic number but different
Mass numbers (same Z, different A) Same number of protons but different number of neutrons
Dalton’s theory
Proposed 3 hypotheses to explain laws of conservation of mass and definite proportions
Dalton’s 3 laws
- Each element is compost of tiny indivisible particles called atoms
- Chemical combination is simply the binding of a definite, small whole number of atoms of each of the combing elements in a fixed ratio to make 2 molecule to form a compound.
3 no atoms are gained, lost, or changed in identity during a chemical reaction; they are just rearranged to produce a new substance
What are daltons 2 theory’s
- Law of conservation of mass- no detectable change in the total mass occurs during a chemical reaction.
- Law of definite proportions- different samples of a pure compound always contain the same elements in the same proportion by mass. (Water is always 11.2% hydrogen and 88.8% oxygen
Who constructed the periodic table
Dmitri Mendeleev 1834-1907, he emphasized that chemical and physical properties are repeated in predictable way
The rows in a periodic table are called
Period and increase by atomic number
The columns in a periodic table are called
Groups or families, elements within a family have similar chemical and physical property
Periodic law is
The properties of elements are periodic functions of their atomic numbers
Metals are
Shiny, lustrous
Malleable, ductile
Electrical and thermal conductor
Left side of periodic table
Non metals are
Variable
Brittle
Non conductor (except graphite)
Located on right side of periodic table
Metalloids (semimetals) are
Shiny, lustrous
Variable
Poor conductors
Located on the stair step of the periodic table
Covalent bonds is a
Group of aroma chemically bonded together into a discreet unit
Covalent=close on the periodic table
Methemoglobinemia
A form of hemoglobin that has been oxidized, changing from ferrous to ferric which cannot bind to oxygen which as a result cannot carry oxygen to tissues
Common element aluminum
Antiperspirant (aluminum chloride) and antacids (aluminum hydroxide)
Common elements of barium
Radio opaque Barium enema (BaSO4)
Common elements for calcium
Excitation and contraction o f muscles Blood clothing (factor IV)
Common elements of Carbon
Organic compounds
Activated charcoal to absorb toxic material
Common elements for chlorine
Disinfectant as sodium hypochlorite (NaOCl) Clorox
Common elements of copper
Wilson’s disease (increased copper)
Common elements of fluorine
Strengthens teeth
Present in inhalation anesthetics (isoflurane, enflurane)
Common elements for helium
Coolant in MRI instruments
Common elements for hydrogen
Most abundant atom
Responsible for body pH
Common elements for iodine
Topical antiseptic
Requires for synthesis of thyroid hormones
Common elements for iron
Fe++ ferrous and Fe +++ ferric
Transport O2 in Hb
Methemoglobinemia tx iv methylene blue
Common elements for lithium
Bipolar disorder
Common elements for magnesium
Mag sulfate
Common elements for mercury
Used in sphygmomanometers, thermometers
Common elements of nitrogen
80% of air Nitrous oxide (N2O) anesthetic gas
Common elements for oxygen
20% of air
Production of ATP
O3 ozone protects skin cancer
Common elements of phosphorous
Present in DNA, RNA, and ATP
Common elements of potassium
Most abundant intracellular ion
Muscle contraction, nerve conduction
Common elements of sodium
Most abundant extra cellular ion
Determines plasma osmolarity and volume
Common elements of silicon
Breast implants
Common elements of silver
Dental fillings
Common elements of silver
Found in cytochrome oxidase
Common elements of titanium
Prosthetic implants
Common elements of zinc
Calamine lotion and sun blocks (zinc oxide)
Ionic compounds are held together by
Ionic bonds - attraction of oppositely charged ions
In a solid state, ionic compounds form
Crystalline lattices
Cations are attracted to all neighboring anions not just one
Thus there is no discrete ionic “molecule”
Chemical bond is an
Energy relationship between the electrons of the reacting atoms
Bonds are formed using the electrons in the outermost energy level
Valence shell is
Outermost energy level containing chemically active electrons
Octet rule (rule of 8)
Except for the first shell which is full with 2 electrons, atoms interact in a manner to have 8 electrons in their valence shell
What are 3 types of chemical bonds
Ionic
Covalent
Hydrogen
Ionic bonds are
Chemical bonds that form between two atoms that transfer one or more electrons from one atom to the other
Form crystals instead of molecules
NaCl is a crystal- large structures of cations and anions held together by ionic bonds
Anion is an
Electron acceptor carrying a net negative charge due to an extra electron
Cation is an
Electron donor carrying a net positive charge due to the loss of an electron
Covalent bonds are
Bonds that form when electrons are shared between 2 atoms
Can be doubled or tripled bonds
Hydrogen bonds are
Weak attractions that form between partially charged atoms found in polar molecule
Common in dipoles such as water
Responsible for surface tension in water
Hydrogen bonds tend to collapse the lunch
Ions are
An atom with a charge, cannot cross cell membrane
Cations - positive, formed by loss of electron, metals
Anion- negative, form from gain of electron, nonmetals
How can we get ions to cross cell membrane?
Check pH, has to be non ionic to cross
Desiccant is
The anhydrous form of a component d that has a strong tendency to form a hydrate, and is used to scavenge the last traces of wager from a system.
Most common is silica gel (SiO2)
Addition of water to a desiccant is a reversible process so saturated desiccants can be used as moisturizers
Moles is an
Amount of substance that contains exactly as many particles as 12.00 grams of carbon
This number is called Avogadro’s number
Particles could mean molecules, atoms, ions, or electrons
Molecular mass is
The sun if they masses of the component atoms
Avogadro’s number
6.02 x 10^23
