Review Concept Flashcards
SI base units are fundamental units of measurement in what international system?
International System of Units (SI)
these units form the foundation for all measurements in science and engineering
SI base units
How many SI base units are there?
7
Give the seven SI base units following this format: Base Quantity — Name — Symbol
Time — second — s
Length — metre/meter — m
Mass — kilogram — kg
Electric current — ampere — A
Thermodynamic temperature — kelvin — K
Amount of substance — mole — mol
Luminous intensity — candela — cd
The duration of 9,192,631,770 periods of the radiation corresponding to the transition between two hyperfine levels of the ground state of the cesium-133 atom
Time
The distance light travels in vacuum in 1/299,792,458 of a second
Length
Defined by fixing the numerical value of the Planck constant (h) to 6.62607015 × 10^-34 when expressed in J•s
Mass
The flow of 1/1.602176634 × 10^-19) elementary charges per second
Electric current
Defined by fixing the numerical value of the Boltzmann constant (k) to 1.380649 × 10^-23 when expressed in J•K^-1
Thermodynamic temperature
The amount of substance containing exactly 6.02214076 × 10^23 elementary entities
Amount of substance
The luminous intensity, in a given direction, of a source that emits monochromatic radiation of frequency 540 x 10^12 Hz and that has a radiant intensity in that direction of 1/683 watt per steradian
Luminous intensity
units of measurement in the International System of Units (SI) that are formed by combining SI base units
SI derived units
used to measure various physical quantities and are derived from the seven SI base units through mathematical operations
SI derived units
mixture of two or more components that form a homogenous mixture
Solution
the dissolved agent of a solution
Solute
the component in which the solute is dissolved
Solvent
the solute when it is a liquid and will form a solution with a solvent over any concentration range
Miscible
measure of the average kinetic energy of particles in a substance
Temperature
• Scale starts at absolute zero
• Used primarily in scientific work
• No degree symbol is used
Kelvin (K)
commonly used in everyday life in most countries
Celsius (°C)
freezing point of water at standard pressure
0°C
boiling point of water at standard pressure
100°C
commonly used in the United States for everyday measurements
Fahrenheit (°F)
freezing point of water in fahrenheit
32°F
boiling point of water in fahrenheit
212°F
• Starts at absolute zero, like Kelvin
• Used in some engineering applications in the US
Rankine (R)
mostly obsolete, but still used in some food production
Réaumur (°Ré)
freezing point of water in Réaumur (°Ré)
0ºRé
boiling point of water in Réaumur (°Ré)
80°Ré
most commonly used in scientific and pharmaceutical applications
Celsius and Kelvin
preferred for precise scientific work due to its relation to absolute zero
Kelvin
mass of a unit volume of a material substance
Density
also called relative density, ratio of the density of a substance to that of a standard substance
Specific gravity
used to convert units of grams and milliliters
Specific gravity
Concentrations of solutions can be expressed in terms of? molarity (M), Molality (m), Normality (N), Mole fraction, Percentage strength (%, w/w, %w/v, v/v), Milliequivalents (mEq), part per million (ppm), parts per billion (ppb), and Osmolarity (Osm, mOsm).
molarity (M)
Molality (m)
Normality (N)
Mole fraction
Percentage strength (%, w/w, %w/v, v/v)
Milliequivalents (mEq)
part per million (ppm)
parts per billion (ppb)
Osmolarity (Osm, mOsm)
forces of attraction within the molecule while intermolecular forces are forces of attraction between molecules
Intramolecular Forces
• Transfer of electrons between a nonmetal & a metal
• observed in formation of salts
Ionic Bond
• sharing of electrons between two nonmetals
• observed in organic compounds
Covalent Bond
• Molecules are polar with permanent polar dipoles
Keesom Forces (orientation effect) or Dipole-dipole
• transient dipole induced by a permanent dipole
• polar molecules produce temporary electric dipole in nonpolar molecules
Debye Forces (induction effect) or Dipole-induced dipole
• induce polarity between non polar molecules
• responsible for liquefaction of gases
London Forces (dispersion effect) or Induced dipole- induced dipole
• Because of the small size of a hydrogen atom and its large field, it can move in close to the electronegative atom (fluorine, oxygen, or nitrogen) and form an electrostatic connection.
• electrostatic interaction of H with highly electronegative atoms (S, N, CL, F, O)
• accounts for unusual properties of water
Hydrogen bond or hydrogen bridge
• Strong forces between counter ions
lon-lon Interactions
• polar molecules are attracted to either positive or negative charges
• occurs when salt is dissolved in a polar solvent
• solubility if crystalline substances in H20
Ion-Dipole Interaction
• induced by close proximity of a charged ion to a non-polar molecule
• responsible for the solubility of non-polar molecules
Ion-Induced Dipole
The units that constitute the crystal structure can be atoms, molecules, or ions. The sodium chloride crystal, consists of a cubic lattice of sodium ions interpenetrated by a lattice of chloride ions, the binding force of the crystal being the electrostatic attraction of the oppositely charged ions.
Crystalline solids
temperature at which a liquid pass into the solid state
freezing point
the heat required to increase the interatomic or intermolecular distances in crystals, thus allowing melting
Heat of fusion
when a substance exists in more than one crystalline form
Polymorphism
In organic compounds, the molecules are held together by what?
van der Waals forces and hydrogen bonding
they tend to flow when subjected to sufficient pressure over a period of time and they do not have definite melting points
Amorphous Solids
The pressure of the saturated vapor above the liquid is then known as the
equilibrium vapor pressure
When the rate of condensation equals the rate of vaporization at a definite temperature, the vapor becomes saturated and a dynamic equilibrium is established.
Vapor Pressure
If a liquid is placed in an open container and heated until the vapor pressure equals the atmospheric pressure, the vapor will form bubbles that rise rapidly through the liquid and escape into the gaseous state.
Boiling
temperature at which the vapor pressure of the liquid equals the external or atmospheric pressure
boiling point
temperature at which a liquid transitions into a gas
Boiling point
nonpolar molecules
Normal Hydrocarbons (Alkanes)
Normal Hydrocarbons (Alkanes) main intermolecular force
London Dispersion Forces (LDFs)
polar molecules due to the Q-H bond and can participate in hydrogen bonding along with LDFs
Simple Alcohols
even more polar than alcohols due to the presence of a carboxyl group (COOH)
Carboxylic Acids
Have a positive and negative end due to uneven sharing of electrons that allows them to participate in dipole-dipole interactions where the positive end of one molecule attracts the negative end of another
Polar molecules
Have a relatively even distribution of electrons, resulting in weak LDFs as the main intermolecular force
Nonpolar molecules
states that at constant temperature, the pressure of a gas is inversely proportional to its volume
Boyle’s Law
states that at constant pressure, the volume of a gas is directly proportional to its absolute temperature (temperature in Kelvin)
Charles’s Law
if you squeeze a gas into a smaller container (decrease volume), the pressure of the gas will increase proportionally (and vice versa)
Boyle’s Law
as you heat a gas (increase temperature), its volume will expand proportionally (and vice versa)
Charles’s Law
states that at constant volume, the pressure of a gas is directly proportional to its absolute temperature
Gay-Lussac’s Law
as you heat a gas in a sealed container (constant volume), the pressure of the gas will increase proportionally (and vice versa)
Gay-Lussac’s Law
states that at constant pressure and temperature, equal volumes of ideal gases contain the same number of molecules
Avogadro’s Law
if you have two containers of different gases at the same pressure and temperature, the container with the larger volume will have a proportionally larger number of gas molecules
Avogadro’s Law
a powerful tool that combines Boyle’s Law, Charles’s Law, and Gay-Lussac’s Law into a single equation. It states that for a fixed amount of gas (meaning the number of moles, n, remains constant).
Combined Gas Law
takes the combined gas law one step further by introducing the concept of the universal gas constant (R). It describes the behavior of ideal gases, which are hypothetical gases that perfectly obey the kinetic molecular theory.
Ideal Gas Law
Gases can be liquefied under high pressures in a closed chamber as long as the chamber is maintained below the critical temperature. When the pressure is reduced, the molecules expand and the liquid reverts to a gas.
Aerosols
material that is liquid under the pressure conditions existing inside the container but that forms a gas under normal atmospheric conditions
Propellant
These devices deliver medication as a pressurized aerosol
Metered Dose Inhalers (MDIs)
convert liquid medication into a mist for inhalation
Nebulizers
often contain desiccant pouches to absorb moisture
Blister Packs
Many antibiotics and other drugs are produced through it, where microorganisms grow in a controlled environment
fermentation
This process removes water from a product by sublimation
Lyophilization (Freeze Drying)
This analytical technique separates and identifies volatile compounds in a mixture
Gas Chromatography (GC)
The combined gas law helps determine the appropriate flow rate and concentration of anesthetic gases to be delivered to patients based on their lung volume and other physiological parameters.
Anesthetic Gas Delivery
a unique phase of matter that exhibits properties intermediate between those of conventional liquids and crystalline solids
Liquid Crystalline
Type of LC phases that is the most common, with rod-shaped molecules aligned along the director but lacking positional order
Nematic
Type of LC Phases in which molecules are also parallel, layered and have some degree of positional order within each layer
Smectic:
Similar to nematic but in this type of crystal the molecules are parallel but arranged in layers
Cholesteric:
Microscopic spheres with a bilayer membrane structure similar to cell membranes
Liposomes
can be used to encapsulate drugs and enhance their solubility, stability, and delivery to target sites
Nanoparticles
LC materials can be designed to respond to specific stimuli (e.g., temperature, light) to release drugs in a controlled manner.
Controlled release
Cholesteric liquid crystals can be used in biosensors for rapid detection of diseases or biological molecules.
Diagnostic Applications
