Chpters 1-5 Flashcards
(26 cards)
A measure of the agreement of replicate measurements
Precision
Prediction of the outcome
Sensitivity
Degree of doubt in a single measurment
Uncertainty
Some materials we use everyday, such as sugar, salt, and water. Or substances that consit of only one kind of matter
Pure substances
Contain more than one substance
Mixture
Derived from the original use of this method to separate plant pigments into color blends
Chromatography
What is the equation for the RF value (Retention Factor)
RF= distance traveled by componet spot/ distance traveled by solvent
Ability to interact with a solvent
Affinity
Electrons are transfered between two atoms to form ions
Ionic bonds
Two electrons are shared between 2 atoms
Covalent bond
Bonds between the atoms or ions in the substance
Intramolecular forces
Attractive forces between the molecules that are external to the molecule itself
Intermolecular
The degree of agreement b/w the true value and measured value
Accuracy
Electrons are transfered; ions of opposite charge are attracted to each other to form crystalline solids. These solids exhibt medium yo high melting points. Thyre non conductive in the solid state but dissolve in polar solvents to produce ions that conduct electricity in solution
Ionic
Electrongs are shared within the molecule. The predominate intermolecular forces are non-polar interactions which are relatively weak and result in very litttle attraction between molecules. Thy tend to be soft and exhibit very low melting points. Thyre soluable in non polar solvents like hexane, but insoluble in polar solvents like water
Non-polar covalent
Electrons are unequally shared, resulting in a slight difference in charge from one atom in the molecule to another. The greater the differences in electronegativity, the more polar the molecule tends to be. Polar intermolecular forces are stronger than non polar so the melting points are low to moderate. Thy tend to be soluble in polar and insoluble in non polar
Polar covalent
Electrons tend to be shared equally;unlike molecular compounds all the atoms in these compounds are covalently bonded to adjacent atoms. The intramolecular bonding forces are difficult to break, so these materials tend to be hard exhibit very high melting points, are not soluble in any solvent and are non conductive
Network covalent
Does not fit the covalent/ionic scheme. Describes bonding in elemental metals and alloys which positively charged nuclei are suspended in a sea of negative electrons. These substances are not soluble and conduct electricity in the solid state
Metallic
Is determined only by the arrangement of bonding electrons around the centeal atom
Molecular geometry
Is determined by the total number of electron clouds( bonding pairs or non bonding e- pairs) and how they are arranged accoriding to VSEPR theory to minimize repulsive energies
Electron pair geometry
Based on negatively charged electrons will repel from one another and that electron pairs when bonding or non bonding will be oriented around
Vsepr
Water molecules are incorporated into the crystal lattice of the compound in such a way that it the water is chemically bound…. Many solids, especially inorganic salts occur natually as…
Hydrates
Absorb water from humid air
Dessicant
All water has been removed
Anhydrous
