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Chem 110 Exam 2
Chemical Bonds & Chemical Aaccounting
Question | Answer |
---|---|
Na+ ions and Cl- have opposite charges and attract each other. What is the resulting reaction? | an ionic bond |
Ionic compounds are held together by ionic bonds and exist in a? | crystal |
In reacting chemically, atoms tend to gain or lose or share electrons so as to have eight valence electrons. This is known as the | Octet rule |
?lose electrons to take on the electron structure of the previous noble gas. In doing so, they form positive ions (cations). | Metals |
?tend to gain electrons to take on the electron structure of the next noble gas. In doing so, they form negative ions (anions). | Nonmetals |
The charge of a cation from the representative elements is the same as the family number. | Cation charge |
The charge of an anion from the representative elements is equal to the family number – 8. | Anions |
Many nonmetallic elements react by ? rather than by gaining or losing electrons. | Sharing electrons |
When two atoms share a pair of electrons, a ? is formed. | covalent bond |
Atoms can share one, two, or three pairs of electrons, forming ?, ?, and ? bonds. | single, double, triple |
?compounds are named by using a prefix to denote the number of atoms. | Binary Covalent |
? is a measure of an atom’s attraction for the electrons in a bond. | Electronegativity |
When two atoms with differing electro-negativity form a bond, the bonding electrons are drawn closer to the atom with the higher electro-negativity. Such a bond exhibits a separation of charge and is called a | Polar Covalent bond |
? are groups of covalently bonded atoms with a charge. | Polyatomic Ions |
An atom or molecule with an unpaired electron is known as a ? | Free radical |
The theory predicts the shape of molecules and polyatomic ions based on repulsions of electron pairs on central atoms. | Valence Shell Electron Pair Repulsion (VSEPR) |
? dissolve in water through ion-dipole interactions. | Ionic Substances |
? represent the sentences in the language of chemistry. They are the means of communicating a chemical change using the symbols and formulas to represent the elements and compounds involved in a chemical reaction. | Chemical Equations |
? are the species present before the reaction. | Reactants |
?are the species present after the reaction: | Products |
?are numbers used to balance a chemical equation. | Coefficients |
: When all measurements are made at the same temperature and pressure, the volumes of gaseous reactants and products are in a small whole-number ratio. | Law of Combined Volumes |
: When measured at the same temperature and pressure, volumes of all gases contain the same number of molecules. | Avogadro’s hypothesis |
is defined as the number of atoms in a 12-g sample of carbon-12 and is: 6.02 x 1023 | Avogadro's number |
A ? is defined as the amount of a substance that contains 6.02 x 1023 particles. | mole (mol) |
? is the average mass of a formula unit relative to that of a carbon-12 atom | Formula Mass |
It is simply the sum of the ? for all atoms in a formula. | atomic masses |
If the formula represents a molecule, often the term ? is used. | Molecular mass (molar mass) |
?:One mole of any gas occupies a volume of 22.4 L at standard temperature and pressure (STP). | Molar Volume of a gas |
?is defined as 1 atmosphere (atm) of pressure and a temperature of 0 oC. | STP |
?involves the quantitative relationship between reactants and products in a balanced chemical equation. | Stoichiometry |
The ? of a balanced chemical equation represent ?. | Coefficients. moles |
The amount of solute in a given amount of solvent is defined as? | Solution Concentration |
A ? contains relative small amounts of solute in a given amount of solvent. | dilute solution |
A ? contains relatively large amounts of solute in a given amount of solvent. | Concentrated Solution |
? is defined as the moles of solute per liter of solution. | Molarity (M) |