Use LEFT and RIGHT arrow keys to navigate between flashcards;
Use UP and DOWN arrow keys to flip the card;
H to show hint;
A reads text to speech;
49 Cards in this Set
- Front
- Back
|
What is an ionic bond? |
Result from the transfer of electrons from one element to another. * Form between a metal on the left side of the periodic table and a nonmetal on the right side. |
|
|
What is a covalent bond? |
Result from the sharing of electrons between two atoms. *Formed when two nonmetals combine, or when a metalloid bonds to a nonmetal. |
|
|
What is an ionic compound? |
They are composed of positively and negatively charged ions held together by strong electrostatic forces. |
|
|
What are electrostatic forces? |
The electrical attraction between oppositely charged ions. |
|
|
What are covalent compounds? |
They are composed of individual molecules, discrete groups of atoms that share electrons. |
|
|
What is bonding? |
It is the joining of two atoms in a stable arrangement. |
|
|
What is a molecule? |
A compound or element containing two or more atoms joined together with covalent bonds. |
|
|
What are cations? |
They are positively charged ions. They have fewer electrons than protons. |
|
|
What are anions? |
They are negatively charged ions. An anion has more electrons than protons. |
|
|
What do metals form? |
Cations. By losing one, two, or three electrons, an atom forms a cation with a completely filled outer shell of electrons. *Metals in groups 1A, 2A, 3A, the group number = the charge on the cation. |
|
|
What do nonmetals form? |
Anions. By gaining one, two, or sometimes three electrons, an atom forms an anion with a completely filled outer shell of electrons. * In groups 5A, 6A, 7A, the anion charge = 8 - the group number. |
|
|
What is the octet rule? |
A main group element is especially stable when it possess on octet of electrons in its outer shell. |
|
|
What must the sum of the charges in an ionic compound always be? |
Zero overall. |
|
|
How to write a formula for an ionic compound: Step 1 |
- Identify which element is the cation and which is the anion.
|
|
|
How to write a formula for an ionic compound: Step 2 |
Determine how many of each ion type are needed for an overall charge of zero. - Write a subscript for the ion that is equal to the magnitude of the charge on the opposite ion. |
|
|
How to write a formula for an ionic compound: Step 3 |
- To write the formula, place the cation first and then the anion, and omit charges. |
|
|
What is a chemical nomenclature? |
Assigning an unambiguous name to each compound. |
|
|
How are cations of main group metlas named> |
They are given the name of the element from which they are formed. |
|
|
How are metals that are able to form two different cations named in the systematic method? |
Follow the name of the cation by a Roman numeral in parentheses to indicate its charge. Ex. Cu2+ = Copper(II) |
|
|
How are metals that are able to form two different cations named in the common method? |
Use the suffix -ous for the cation with the lesser charge, and the suffix -ic for the cation with the higher charge. These suffixes are often added to the Latin names of the elements. Ex. Cu+ = Cuprous Cu2+ = Cupric |
|
|
How are anions named? |
They are named by replacing the ending of the element name by the suffix -ide. Ex. Chlorine - Chloride |
|
|
How to name ionic compounds with cations from main group metals? |
Name the cation and then the anion. * Do not specify how many ions of each type are needed to balance the charge. |
|
|
How to name an ionic compound that contains a metal with variable charge: |
1. Determine the charge on the cation. 2. Name the cation and anion 3. Write the name for the cation first, then the anion. |
|
|
How to derive a formula from the name of an ionic compound: |
1. Identify the cation and the anion and determine their charges. 2.Balance charges. 3. Write the formula with the cation first, and use subscripts to show the number of each ion needed to have zero overall charge. |
|
|
Ionic compounds have very _____ melting points. |
High |
|
|
Ionic compounds have extremely _____ boiling points. |
High |
|
|
Many ionic compounds are _____ in water? |
Soluble. |
|
|
What is a polyatomic ion? |
It is a cation or anion that contains more than one atom. |
|
|
What do most polyatomic ions end in? |
-ate * -ite is used for an anion that has one fewer oxygen atom than a similar anion named with the -ate ending. * When two anions differ in the presence of a hydrogen, the word hydrogen or the prefix bi- is added to the name of the anion. |
|
|
How to write the formula for ionic compounds with polyatomic ions? |
Same as writing a formula for an ion with a single charged atom. * Parentheses are used around the polyatomic ion when you need a subscript. |
|
|
What symbol do we use to represent a two-electron bond? |
A solid line between two element symbols. |
|
|
What are diatomic molecules? |
They contain just two atoms. Hydrogen (H2), Nitrogen (N2), Oxygen (O2), Fluorine (F2), Chlorine (Cl2), Bromine (Br2), Iodine (I2). |
|
|
What are nonbonded electron pairs or lone pairs? |
The unshared electron pairs in a covalent bond. |
|
|
What are Lewis structures? |
Electron-dot structures for molecules. They show the location of all valence electrons in a molecule, both the shared electrons in bonds, and the nonbonded electron pairs. |
|
|
How many covalent bonds will neutral molecules have? |
- Atoms with one, two, or three valence electrons generally form one, two, or three bonds, respectively. - Atoms with four or more valence electrons form enough bonds to give an octet. 8 - number of valence electrons. |
|
|
What are three general rules for drawing Lewis structures? |
1. Draw only the valence electrons. 2. Give every main group element (except hydrogen) an octet of electrons 3. Give each hydrogen two electrons. |
|
|
How to name a covalent molecule with two elements: |
1. Name the first nonmetal by its element name and the second using the suffix -ide. 2. Add prefixes to show the number of atoms of each element. - The prefix mono- is omitted when only one atom of the first element is present, but retained for the second element. |
|
|
What is a group? |
An atom or a lone pair of electrons. |
|
|
What is the valence shell electron pair repulsion (VSEPR) theory? |
The most stable arrangement keeps these groups as far away from each other as possible. |
|
|
What is the arrangement of an atom surrounded by two groups? |
It is linear and has a bond angle of 180 degrees. |
|
|
What is the arrangement of an atom surrounded by three groups? |
It is trigonal planar and has bond angles of 120 degrees. |
|
|
What is the arrangement of an atom surrounded by four groups? |
It is tetrahedral and had bond angles of 109.5 degrees. |
|
|
What is electronegativity? |
A measure of an atom's attraction for electrons in a bond. It tells us how much a particular atom "wants" electrons. -Increases left to right, decreases top to bottom. |
|
|
What is a nonpolar bond? |
Two identical atoms are bonded together, each atom attracts the electrons in the bond to the same extent. The electrons are equally shared. - Less than 0.5 unites |
|
|
What kind of bond is a carbon-carbon bond? |
Nonpolar |
|
|
What are polar or polar covalent bonds? |
Bonding between atoms of different electronegativity that results in unequal sharing of electrons. - S+ is given to the less electronegative atom - S- is given to the more electronegative atom. - 0.5 - 1.9 units |
|
|
When a molecule contains zero or one polar bond this can be said" |
- A molecule with no polar bonds is a nonpolar molecule - A molecule with one polar bond is a polar molecule. |
|
|
With covalent comounds that have more than one polar bond? |
- If the individual bond dipoles do not cancel, the molecule is polar - IF the individual bond dipoles cancel, the molecule is nonpolar. |
|
|
Whats the polarity of a molecule that has two or more polar bonds? |
1. Identify all polar bonds based on electronegativity differences. 2. Determine the shape around individual atoms by counting groups. 3. Decide if individual dipoles cancel or reinforce. |
