Exam 1 – Chemistry Test Questions – Flashcards
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Unlock answers 106Left side of the zigzag line in the periodic table (except for hydrogen) Hard, solide, malleable(except Hg, which is liquid) Conducts electricity, not brittle
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| Metals |
Right side of the zigzag line in the periodic table Gases Not malleable or brittle Insulators of electricity |
| Nonmetals |
Tend to lie along the zigzag line in the periodic table Properties of metals and nonmetals |
| Metalloids |
| React with water to produce acids (-1 anions) |
| Halogens |
column 1A Form an alkali solution when combined with water (+1 cations when in water) |
| alkali metals |
column 2A +2 cations with water Most insoluable in water |
| alkaline earth metals |
| Chemically inert |
| Nobel gases |
Independent of sample size Temperature Melting Point Density |
| Intensive properties |
Dependent on sample size Length Volume |
| Extensive properties |
Amount of matter in an object All matter has this |
| Mass |
| Describes anything with a physical presence - anything you can touch, taste, or smell |
| Matter |
Measures the force with which gravity pulls on an object
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| Weight |
How close to the true value a given measurement is Single measurement: percent error Series of measurements: average
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| Accuracy |
How well a number of independent measurements agree with each other. Characterized by the standard deviation. |
| Precision |
the number of meaningful digits in a measured or calculated quantity. They come from uncertainty in any measurement Generally the last digit in a reported measurement is uncertain Exact numbers and relationships (7 days in a week, 30 students in a class) effectively have an infinite number of this |
Significant figures
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Mass is neither created nor destroyed in chemical reactions Atoms do nto mutate in reactions |
| Law of Conservation of Mass |
Differenct samples of a pure chemical substance always contain the same proportion of elements by mass A pure substane will always have the same type and mass of atoms |
| Law of Definite Proportions |
| Elements are made up of tiny particles |
| Atoms |
Matter is made up of atoms, atoms combine in whole numbers, in reactions, atoms rearrange Each element is characterized by the mass of its atoms. Atoms of the same element have the same mass, but atoms of different elements have different masses Chemical combination of elements to make different substances occurs when atoms join together in small whole-number ratios Chemical reactions only rearrange the way that atoms are combined, the atoms themselves don't change |
| Dalton's Atomic Theory and the Law of Multiple Proportions |
| Elements can combine in different ways to form different substances, whose mass rations are small whole-number multiples of each other. |
| Law of Multiple Proportions |
| J.J. Thomson proposed that cathode rays must consist of tiny negatively charged particles called |
| Electrons |
Rutherford bombarded gold foil with alpha particles. Although most of the alpha particles passed through the foil undeflected, approximately 1 in every 20,000 particles were deflected. A fraction of those particles were deflectedc back at an extreme angle. He proposed that the atom must consist mainly of empty space with the mass concentrated in a tiny central core. His experiment showed that the mass of the atom is found in the |
| Atomic Nucleus |
| Alpha rays are scattered only when they hit nucleus. The nucleus must be very small relative to the atom volume |
| Interpretation of Rutherford's Results |
The mass of an atom is in the nucleus The proton and neutrons have equal mass The electron is negative The proton is positive |
| Structure of Atoms |
| Number of protons in an atom's nucleus. Equivalent to the number of electrons around the atom's nucleus. |
| Atomic Number |
| The sum of the number of protons and the number of neutrons in an atom's nucleus. |
| Mass Number |
| Atoms with identical atomic numbers but different mass numbers |
| Isotope |
| The weighted average of the isotopic masses of the element's naturally occurring isotopes |
| Atomic Mass |
| Matter consists of ____, elements or compound |
| Pure substances |
| Mixtures are |
| hetero or homogeneous |
| Contain atoms connected by covalent bonds (collection of like molecules is a pure molecular compound) |
| Molecules |
| Results when two atoms share several (usually two) electrons.; Typically a nonmetal bonded to a nonmetal. |
| Covalent Bond |
| A transfer of one or more electrons from one atom to another.; An electrostatic attraction between charged particles.; Typically a metal bonded to a nonmetal. |
| Ionic Bond |
A class of compounds Positive and negative atoms associate to form a neutral salt |
| Ionic compounds |
| A charged particle |
| Ion |
| A positively charged particle.; Metals tend to form these |
| Cation |
| A negatively charged particle.; Nonmetals tend to form these |
| Anion |
| ____ are not individual molecules, rather a neutral aggregate of positive and negative ions |
| Salts |
Form when metals give up electrons to nonmetals The metal cation is positive and the nonmetal anion is negative |
| Binary salts |
Class of compounds ____ release protons (H+) and ____ release hydroxide (OH-) |
| Acids and bases |
Compounds that are easiest to name Identify the metal cation and its charge for the main group 1A to 3A the cation charge is the group number |
| Binary ionic compounds |
Identify the nonmetal anion The charge for atoms from 5A to 7A is group number -8 |
| Naming Ionic Compounds |
| The name must indicate the charge since they vary for most for |
| transition metals |
| Take the name of the element |
| cations |
Take the root of the nonmetal name and ide The salt is the cation name plus the anion name |
| anions |
Fro molecular compounds, the number of each atom type must be given Use prefixes mono, di, tri, tetra, penta, hexa, hepta, etc. |
| Naming binary molecular, covalent compounds |
The first element listed is more cation like and takes the name of the element The second element listed is more anion like and takes the name of the element with an ide modification to the ending |
| Naming binary molecular, covalent compounds |
Named after the anion ite to ous ate to ic |
| Complex acids |
When hydrogen is listed first Neutral The correct number of hydrogens (+) have to be added to make it neutral |
| Acid |
| A balanced chemical equation show that the _____ is adhered to |
| law of conservation of mass |
| Sum of atomic masses of all atoms in a molecule |
| Molecular/Formula Mass |
| Sum of atomic masses of all atoms in a formula unit of any compound, molecular or ionic |
| Formula/Molecular Mass |
| One mole of any substance contains 6.022 * 10^23 formula units |
| Avogadro's Number |
| One mole of any substance is equivalent to its |
| Molecular/Formula Mass |
| The relative proportions in which elements form compounds or in which substances react |
| Stoichiometry |
| The amount actually formed in a reaction |
| Actual Yield |
| The amount predicted by calculations |
| Theorectical Yield |
| (actual yield)/(theorectical yield) * 100 |
| Percent Yield |
| The reactant that is present in limiting amount. The extent to which a chemical reaction takes place depends on this |
| Limiting Reactant |
| Any of the other reactants still present after determination of the limiting reactant |
| Excess Reactant |
The number of moles of a substance dissolved in each liter of solution. (moles of solute)/(liters of solution) |
| Molarity |
| A homogenous (well-mixed) mixture |
| Solution |
| The dissolved substance in a solution |
| Solute |
| The major component in a solution |
| Solvent |
Concentrated solution + solvent = _____ MiVi = MfVf |
| dilute solution |
| A procedure for determing the concentration of a solution by allowing a carefully measured volume to react with a solution of another substance (the standard solution) whose concentration is known |
| Titration |
Expressed by identifying the elements present and giving the mass percent of each (mass atom X)/(formula mass)*100 |
| Percent Composition |
| It tells only the rations of the atoms in a compound |
| Empirical Formula |
| It tells the actual numbers of atoms in a compound. It can be either the empirical formula or a multiple of it. |
| Molecular Formula |
| Sulfide |
| S-2 |
| Sulfite |
| SO3^-2 |
| Sulfate |
| SO4^-2 |
| Nitride |
| N^-3 |
| Nitrite |
| NO2^-1 |
| Nitrate |
| NO3^-1 |
| Phosphide |
| P^-3 |
| Phosphite |
| PO3^-3 |
| Phosphate |
| PO4^-3 |
| Carbide |
| C^-4 |
| Carbonate |
| CO3^-2 |
| Chloride |
| Cl^-1 |
| Hypochlorite |
| ClO^-1 |
| Chlorite |
| ClO2^-1 |
| Chlorate |
| ClO3^-1 |
| Perchlorate |
| ClO4^-1 |
| Bromide |
| Br^-1 |
| Hypobromite |
| BrO^-1 |
| Bromite |
| BrO2^-1 |
| Bromate |
| BrO3^-1 |
| Perbromate |
| BrO4^-1 |
| Iodide |
| I^-1 |
| Hypoiodite |
| IO^-1 |
| Iodite |
| IO2^-1 |
| Iodate |
| IO3^-1 |
| Periodate |
| IO4^-1 |
| Hydroxide |
| OH^-1 |
| Cyanide |
| CN^-1 |
| Cyanate |
| CNO^-1 |
| Hydrogen phosphate |
| HPO4^-2 |
| Hydrogen sulfate |
| HSO4^-1 |
| Bicarbonate |
| HCO3^-1 |
| Ammonium |
| NH4^+1 |
