Module 3 Flashcards
Lewis symbols show…
valence electrons on atoms and ions
chemical bonding is
the attractive force between atoms in a compound
chemical can be classified as
covalent, polar covent, non polar covalent, and ionic
electronegativity is
a measure of the ability of an atom to attract electrons in a chemical bond
the difference in electronegativity is used in classifying what?
the type of chemical bond, i.e. 0.5 and less is non polar covalent; 0.5 to 2.0 is polar covalent; and difference of 2.0 or larger is ionic
monatomic ion
ions consisting of a single atom
polyatomic ions
are composed of two or more atoms bonded together; although bonds to other ions with ionic bonds, they are themselves held together by covalent bonds
In VSEPR theory, the main force that determines the geometry of a molecule is:
repulsion of the electron pairs in the molecule
Ammonia is soluble in water because both ammonia and water molecules are __________. Oil and water don’t mix because oil is __________ and water is __________.
polar; nonpolar; polar
Which of the following rules is not true when drawing Lewis dot structures for covalent molecules?
use the most electronegative atom as the central atom,
A soluble ionic compound may __________ in water to form positive and negative ions, while a soluble covalent compound may __________ but will be a/an __________.
dissociate; dissolve; nonelectrolyte
When no one single Lewis structure can adequately explain the electron distribution in a molecule, we conceptualize the ‘true’ structure as being a combination of all possible Lewis structures and call it a/an __________.
resonance hybrid
Bonds in which electrons are shared unequally (i.e., the electrons spend more time around one atom than around the other) are called:
polar covalent
Which of the following are the correct formulas for these ionic compounds: calcium chloride, sodium fluoride, potassium sulfide?
CaCl2; NaF; K2S
Put these diatomic molecules in order from the most stable to the most reactive: O2, H2, N2.
nitrogen, oxygen, hydrogen; The most stable diatomic molecule is nitrogen, because it has a triple bond. The next in reactivity is oxygen, with a double bond. The most reactive molecule is hydrogen, with a single bond.
What are the three basic molecular shapes that have the following bond angles between their component atoms? 180°, 120°, and 109.5°.
linear, trigonal planar, tetrahedral
Which compound in each of the following pairs of compounds would you expect to have the higher boiling point? nitrogen vs. ammonia; water vs. potassium chloride; ethanol vs. hexane
ammonia; potassium chloride; ethanol, - The forces between ions in ionic compounds are very strong, so the melting and boiling points of these compounds are very high. The forces are quite a bit weaker for polar covalent molecules, and weakest of all for nonpolar covalent molecules, which have the lowest melting points and boiling points. Nitrogen is nonpolar, ammonia is polar; water is polar, potassium chloride is ionic; hexane is nonpolar, ethanol is polar.
solubility is
the maximum amount of solute that dissolves in a given amount of solvent at a specific temperature
Bonds in which electrons are shared unequally (i.e., the electrons spend more time around one atom than around the other) are called:
polar covalent
__________ is a measure of an atom’s ability to attract electrons to itself within a chemical bond. Atoms with the highest values of this quantity are located in the __________ of the periodic table, while those with the lowest values are located in the __________ of the table.
electronegativity; top right area; bottom left area
What are the correct names for these covalent compounds? N2O3, N2O4, N2O, and NO2
dinitrogen trioxide; dinitrogen tetroxide; dinitrogen oxide; nitrogen dioxide
