Unit 3 Study Guide Flashcards
Is water a polar or a nonpolar molecule? Why?
Water is polar because of its uneven charges
What happens when a polar molecule combines with a nonpolar molecule?
The combination will NOT form a solution
What is electronegativity and what is it used for?
Electronegativity is the ability of an ion to attract electrons. It is used to predict the types of bonds that a molecule consists of.
Explain how a nonpolar molecule can have polar bonds.
Polar bonds on opposite sides of a molecule can nullify each other if they are equal, thus making a non polar molecule. Ex: O=C=O
How do you know the number of valence electrons an atom has?
The group number
Where do the radioactive elements begin on the periodic table and what does it mean to be radioactive?
Every atom with an atomic number of 84 (Polonium) or higher is radioactive. Radioactive molecules are highly unstable and undergo radioactive decay.
What are valence electrons?
Electrons on the outermost shell of an atom
What subatomic particles determine chemical properties?
Electrons
When are Roman numerals used in chemical formulas?
To identify the number of valence electrons that a transition metal has
What does the octet rule have to do with noble gases?
Noble gases have a full octet, or 8 electrons on their outer shell.
What does the charge of an ion represent?
The charge of an ion represents the relative number of protons to electrons
What does the octet rule state and how does it apply to ionic versus covalently bonded compounds?
The octet rule states that atoms gain and lose electrons to become stable, which means to have a full valence shell.
What is a salt?
A salt is the product of a reaction between an acid and a base
What types of ions end in -ide?
Anions
What are the elemental characteristics of ionic compounds compared to covalent compounds?
Ionic compounds contain both a metal and a nonmetal while covalent compounds only contain nometals
What is the definition of an ionic bond?
The electrostatic forces that hold ions together in ionic compounds
How can you differentiate between a polar covalent molecule and a nonpolar covalent molecule?
Nonpolar bonds have an equal share of electrons while polar bonds do not.
How does hydrogen bonding affect the physical characteristics of a compound?
The compound turns into an acid
How do you know the charge of a transition metal from its formula?
The Roman numeral to the right of the transition metal
What is the definition of an isotope?
An atom with a different number of protons and neutrons
What types of molecules have Greek prefixes in their names?
Covalent
List all the differences between ionic and covalent compounds including their chemical properties (melting points, conductivity, solubility).
Ionic- high melting, conduct in water, soluble with other ionic compunds
Covalent- low melting, not very conductive, soluble with other covalent compounds
Where are cations versus anions on the periodic table?
Cations- left of carbon group
Anions- right of carbon group
What does it mean when an anion ends in -ate or -ite?
Atoms that end in -ate generally have one more oxygen atom than those that end in -ite
How can an acid be identified by its formula?
Acids have solely hydrogen and no oxygen (ex: HCl) while bases contain hydroxide (ex: NaOH)
When is the prefix hydro- used as opposed to the ending -ic or -ous in naming acids?
Hydro- indicates that a compound has a hydrogen atom and is part of a binary (two word) compound. -ic and -ous are used in oxyacids, which consist of a hydrogen atom, nonmetal, and a varying number of oxygen atoms.
