Chapter 5 Review

Strong electron donors are on the ____ side of the periodic table, while strong electron acceptors are on the ___ side.

1. left 2. right

How many valence electrons does oxygen have? How many more electrons are needed to fill the outermost energy level?

6 valence electrons It needs 2 electrons

How many electrons represent a complete (filled) outermost energy level for elements heavier than Boron (atomic number greater than 5)?

8

molecular formula

A chemical formula that shows the number and kinds of atoms in a molecule, but not the arrangement of the atoms

chemical formula

A combination of chemical symbols and numbers to represent a substance

mixture

A combination of two or more substances that are not chemically combined

What is the difference between a compound and a mixture?

A mixture is made of two or more substances that are not chemically combined where as a compound is made of 2 elements that are chemically combined

anion

A negatively charged ion

compound

A substance made up of atoms of two or more different elements joined by chemical bonds

Name a very reactive group of metals Tell why they are so reactive

Alkali Metals Because they do not occur freely in nature

Write the formula for a molecule containing carbon (C) with an oxidation number +4 and oxygen (O) with an oxidation number of -2

C2O4

Elements that are close together on the periodic table tend to for what kind of compounds?

Covalent

What type of bond holds a water molecule together? How does that affect water's melting and boiling points?

Covalent bonds You don't have to break any covalent bonds in order to melt or boil a molecular substance

Summarize three differences between a covalent compound and an ionic compound

Covalent compound 1. it has a definite shape 2. it has a low melting point 3. it occurs between non-metals Ionic compound 1. it has no definite shape 2. it has a high melting point 3. it occurs between one metal and one non-metal

What is the chemical formula for water? What elements make up this compound? How many atoms of each? How do you know?

H20 Hydrogen and Oxygen 3 Two atoms of the element hydrogen combine with one atom of oxygen through a covalent bond to form water

Name a very reactive group of non-metals Tell why they are so reactive

Halogens Because they are all electronegative

What is so special about hydrogen when it comes to forming bonds?

Hydrogen only has 1 electron so it can make bonds with many other elements.

Elements that are widely separated on the periodic table tend to form what kind of compounds?

Ionic

What is the total electric charge on molecules and compounds?

It is always zero

List 3 examples of a mixture and 3 examples of a compound

Mixtures- sugar & tea, sand & water, and coffee & sugar Compounds- Hydrogen2 + Oxygen2 = Hydrogen Peroxide, Carbon8 + Hydrogen18 = Octane, and Sodium + Chlorine = Salt

Write the formula for a molecule of N3- and H+

NH3

Which group of elements usually don't form chemical bonds Why?

Noble gases Because they have full outermost energy levels.

oxidation number

Positive or negative number that indicates how many electrons an atom has gained, lost, or shared to become stable

cation

Positively charged ion

How does the oxidation number indicate if an electron will be lost or gained by the bonding atom?

Postive- electrons will be lost Negative- electrons will be gained

When atoms form chemical bonds, which of their electrons are involved in the bonds?

The outer valence shell electrons used to form chemical bonds

molecule

The smallest unit of a substance that keeps all of the physical and chemical properties of that substance; it can consist of one atom or two or more atoms bonded together

Each successive column on a period table, going from left to right, not counting the transition elements, has what?

They have oxidation numbers

Why do atoms form compounds instead of existing as single atoms?

To make bonds and fill up every levels

ionic bond

a bond formed by the attraction between oppositely charged ions

metallic bond

a bond formed by the attraction between positively charged metal ions and the electrons around them

covalent bond

a bond formed when atoms share one or more pairs of electrons

a. What is the total of the oxidation numbers for all the atoms in methane? b. Predict the formula for methane c. Is methane an ionic or covalently bonded compound?

a. +1 b. CH4 c. Covalent

Give the most common oxidation number and how many electrons are gained or lost for the following elements: a. oxygen (O) b. boron (B) c. lithium (Li) d. potassium (Na) (K) e. magnesium (Mg) f. aluminum (Al) g. carbon (C) h. iodine (I)

a. -2, gain b. +3, lose c. +1, lose d. +1, lose e. +2, lose f. +3, gain g. +4, or -4, both lose and gain h. -1, gain

Using the periodic table, which is the oxidation number of? a. calcium b. aluminum c. floride

a. 2 b. 3 c. -1

a. How many atoms of carbon are in a molecule of glucose? b. How many atoms of hydrogen are in a molecule of glucose? c. How many atoms of oxygen are in a molecule glucose?

a. 6 b. 12 c. 6

a. what is the total of the oxidation numbers for all the atoms in carbon dioxide? b. Predict the formula for carbon dioxide c. Is carbon dioxide an ionic or covalently bonded compound?

a. 8 b. C2O4 c. Covalent

Using the periodic table: a. Determine the oxidation number Ca and Cl b. Write the chemical formula for calcium chloride

a. Ca+2 Cl-1 b. CaCl2

For each of the formulas for molecules listed below, name each element and how many of atoms of each element are in that molecule: a. C6H12O6 b. CaCO3 c. Al2O3 d. Fe(OH)3

a. Carbon, and carbon has 6 atoms. Hydrogen, and hydrogen has 12 atoms. Oxygen, and oxygen has 6 atoms. b. Calcium, and calcium has one atom. Cobalt, and has three atoms. c. Aluminum, and aluminum has 2 atoms. Oxygen, and oxygen has three atoms. d. Iron, and Iron has one atom. Hydroxide and oxygen has zero, and hydrogen has three. That means Hydroxide has three atoms.

Use he periodic table to determine the type of bond most likely formed between the elements: a. carbon and oxygen b. lithium and fluorine c. carbon and carbon d. carbon and nitrogen

a. covalent b. ionic c. covalent d. covalent

ion

an atom, radical, or molecule that has gained or lost one or more electrons and has a negative or positive charge

valence electrons

an electron that is found in the outer-most shell of an atom and that determines the atom's chemical properties

polyatomic ion

an ion made of two or more atoms

chemical structure

arrangement of atoms in a substance

bond angle

the angle formed by two bonds to the same atom

chemical bond

the attractive force that holds atoms or ions together

empirical formula

the composition of a compound in terms of the relative numbers and kinds of atoms in the simplest ratio

bond length

the distance between two bonded atoms at their minimum potential energy; the average distance between the nuclei of two bonded atoms

hydrogen bond

the intermolecular force occurring when a hydrogen atom that is bonded to a highly electronegative atom of one molecule is attracted to two unshared electrons of another molecule