Carbon Chemistry (8th Grade Chemistry: Chapter 4)
Saturated Hydrocarbons
-All single bonds -Names end in -ane -Maximum # of hydrogens -Examples: butane, methane -Uses: fuels
Unsaturated Hydrocarbons
-Double or triple bonds -Names end in -ene or -yne -Fewer # of hydrogens -Examples: ethene(double bond), ethyne(triple bond) -Uses: fruit ripening, welding
Synthetic
A material that is not formed naturally but is manufactured
Alkynes
Alkynes are the third class of simple hydrocarbons and are molecules that contain at least one triple-bonded carbon pair. Like the alkanes and alkenes, alkynes are named by combining a prefix with the ending "yne" to denote the triple bond. The chemical formula for the simple alkynes follows the expression CnH2n-2.
Alkenes
The second class of simple hydrocarbons, the alkenes, consists of molecules that contain at least one double-bonded carbon pair. Alkenes follow the same naming convention used for alkanes. A prefix (to describe the number of carbon atoms) is combined with the ending "ene" to denote an alkene. Ethene, for example is the two-carbon molecule that contains one double bond. The chemical formula for the simple alkenes follows the expression CnH2n. Because one of the carbon pairs is double bonded, simple alkenes have two fewer hydrogen atoms than alkanes.
Hydrocarbons
The simplest organic chemicals Contain only carbon and hydrogen atoms
The maximum number of bonds a carbon atom can form is _______.
four
The simplest alkane is ________.
methane
The group -COOH is a characteristic of ________.
organic acids
When compounds have the same _______ formula, but different _______ formulas, they are called isomers.
same molecular different structural
Carbon atoms can form _________, _________, and _________.
straight chains, branched chains rings
Unsaturated Hydrocarbon
A hydrocarbon in which one or more of the bonds between carbon atoms is double or triple
Polymer
A large molecule in the form of a chain in which many smaller molecules are bonded together
Subscript
A number in a formula written lower and smaller than the symbol to indicate the number of atoms of an element in a molecule
Alcohol
A substituted hydrocarbon that contains one or more hydroxyl groups
Organic Acid
A substituted hydrocarbon with one or more of the -COOH group of atoms
Isomers
Because carbon can bond in so many different ways, a single molecule can have different bonding configurations. Two molecules can have identical chemical formulas; however, their structural formulas (and thus some chemical properties) are different. These two molecules are called isomers. Isomers are molecules that have the same chemical formula but different structural formulas.
What happens to the number of hydrogen atoms in the molecule as the number of bonds between any two carbon atoms increases?
As the number of bonds between any two carbon atoms increases, the number of hydrogen atoms in the molecule decreases.
Alcohols
Hydroxyl group(-OH) fills in for one or more hydrogens -Alcohols do dissolve in water and tend to be liquids -Examples: CH3OH (methanol) C2H5OH (ethanol) -Uses: beverage, gasoline additive, making plastics and synthetic fibers
Substituted Hydrocarbon
In a substituted hydrocarbon, one or more hydrogens is out, and another element or special group fills in for it.
Functional Groups
In addition to carbon and hydrogen, hydrocarbons can also contain other elements. In fact, many common groups of atoms can occur within organic molecules. These groups of atoms are called functional groups. The existence of the functional group completely changes the chemical properties of the molecule. Ethane, the two-carbon alkane, is a gas at room temperature; ethanol, the two-carbon alcohol, is a liquid.
What is the simplest hydrocarbon?
Methane Methane contains a single carbon atom bonded to four hydrogen atoms
Hydrocarbons
-Hydrocarbons contain hydrogen and carbon -Carbon chains are straight, branched, or rings -Are flammable -Mix poorly with water
The uniqueness of carbon comes from the fact that...
... it can bond to itself in many different ways. Carbon atoms can form long chains, branched chains, and rings. There appears to be almost no limit to the number of different structures that carbon can form. To add to the complexity of organic chemistry, neighboring carbon atoms can form double and triple bonds in addition to single carbon-carbon bonds.
Organic chemicals get their diversity from...
...the many different ways carbon can bond to other atoms.
3 Types of Substituted Hydrocarbons
1) Halogen Compounds 2) Alcohols 3) Organic Acids
Saturated Hydrocarbon
A hydrocarbon in which all the bonds between carbon atoms are single bonds
Substituted Hydrocarbon
A hydrocarbon in which one or more hydrogen atoms have been replaced by atoms of other elements
The group of simple organic molecules that contain only C and H are called ___________.
hydrocarbons
Diamond
a form of the element carbon; the hardest mineral crystal on earth
What do the names of saturated hydrocarbons end in?
-ane
Alkanes
Alkanes are the first class of simple hydrocarbons and contain only carbon-carbon single bonds. The alkanes are named by combining a prefix that describes the number of carbon atoms in the molecule with the root ending "ane". The chemical formula for any alkane is given by the expression CnH2n+2.
Bonds Hydrogens & Carbons
All hydrogens make 1 bond (they only have 1 valence electron!!) so each hydrogen can only have 1 dash attached to it. All carbons must have 4 bonds (they have 4 valence electrons) so each carbon must have 4 dashes attached to it. *This could be 4 single bonds, or a double and 2 singles, or a triple and 1 single. Carbon can make single, double, or triple bonds with other carbons. It can make single or double bonds with oxygen. It can only make single bonds with hydrogen.
Hydroxyl Group
An example of a functional group is the hydroxyl functional group. The hydroxyl group consists of a single oxygen atom bound to a single hydrogen atom (-OH). The group of hydrocarbons that contain a hydroxyl functional group is called alcohols. The alcohols are named in a similar fashion to the simple hydrocarbons, a prefix is attached to a root ending (in this case "anol") that designates the alcohol.
Ester
An organic compound made by chemically combing an alcohol and an organic acid
Hydrocarbon
An organic compound that contains only carbon and hydrogen
Valence Electrons of Carbon
Carbon (C) appears in the second row of the periodic table and has four bonding electrons in its valence shell. Similar to other non-metals, carbon needs eight electrons to satisfy its valence shell. Carbon therefore forms four bonds with other atoms (each bond consisting of one of carbon's electrons and one of the bonding atom's electrons). Every valence electron participates in bonding; thus, a carbon atom's bonds will be distributed evenly over the atom's surface.
What are carbohydrates made up of?
Carbon, hydrogen, and nitrogen
Organic Acids
Contain 1 or more CARBOXYL group(-COOH) in place of hydrogen(s) -Taste sour -Names end in "-ic acid" -Examples: citric acid, acetic acid
True or False: A hydrocarbon with only single bonds in its carbon chain is called an unsaturated hydrocarbon.
False
True or False: When molecules have the same number and type of atoms, they must have the same structure.
False
Organic Compounds
Most compounds that contain carbon
Graphite
a form of the element carbon in which carbon atoms form flat layers
Organic chemistry is broadly defined as: a.) all of the choices b.) the chemistry of metallic compounds c.) the chemistry of substances produced by living d.) organisms the chemistry of the compounds that contain carbon and hydrogen
d.) organisms the chemistry of the compounds that contain carbon and hydrogen
Carboxyl Group
A -COOH group, found in organic acids
Hydroxyl Group
A combination of an oxygen atom and a hydrogen atom An -OH group, found in alchohols
Molecular Formula
A combination of chemical symbols that represent the elements in each molecule of a compound
Structural Formula
A description of a molecule that shows the kind, number, and arrangement of atoms
Fullerene
A form of the element carbon that consists of carbon atoms arranged in a repeating pattern
Halogen Compounds
A halogen substitutes for at least 1 hydrogen Example: Cl2F2 (Freon)
We do we use structural formulas?
Sometimes, a certain molecular formula could have more than one form. Structural formulas show what the molecule looks like.
Monomer
One molecule that makes up the links in a polymer chain
Isomer
One of a number of compounds that have the same molecular formula but different structures
Organic Compounds
Organic Compounds all contain carbon "Organic" means "of living things" Properties: 1.) Low melting and boiling points (tend to be liquids and gases at room temp.) 2.) Smelly 3.) Don't mix with water 4.) Don't conduct electricity
How to Write a Molecular Formula
Step 1: Write the symbol of the element (carbon is written first) Step 2: Use subscripts to write the number of atoms of each element after the symbol NOTE: If there is one of the element, you don't write the one (like in math with exponents, an exponent of 1 is understood).
Structural Formulas
Structural formulas show the KIND of atom, NUMBER of atoms, and ARRANGEMENT of atoms
The simple alkanes share many properties in common.
The simple alkanes all enter into combustion reactions with oxygen to produce carbon dioxide and water vapor. In other words, many alkanes are flammable. This makes them good fuels. For example, methane is the principle component of natural gas, and butane is common lighter fluid.
Simple Hydrocarbons
The simplest hydrocarbons are those that contain only carbon and hydrogen. These simple hydrocarbons come in three varieties (alkanes, alkenes, and alkynes) depending on the type of carbon-carbon bonds that occur in the molecule.
Organic Chemistry
To understand life as we know it, we must first understand a little bit of organic chemistry. Organic molecules contain both carbon and hydrogen. Though many organic chemicals also contain other elements, it is the carbon-hydrogen bond that defines them as organic. Organic chemistry defines life. Just as there are millions of different types of living organisms on this planet, there are millions of different organic molecules, each with different chemical and physical properties. There are organic chemicals that make up your hair, your skin, your fingernails, and so on. The diversity of organic chemicals is due to the versatility of the carbon atom.
How to Write Structural Formulas
Use the symbol to represent the elements present. With hydrocarbons, start with carbon. Draw however carbons there are in a chain (to start). Use dashes to represent bonds. A single dash for a single bond, double dash for double bond, and triple dash for triple bond. Fill in hydrogens or other elements.
All hydrocarbons a.) burn easily b.) mix well with water c.) contain hydrogen, carbon, and oxygen d.) have ring shaped molecules
a.) burn easily
A compound containing only carbon and hydrogen and that has no double bonds is called an:
alkane
Pure carbon exists as all the following forms EXCEPT_______. a.) graphite b.) methane c.) fullerene d.) diamond
b.) methane
Many organic compounds... a.) have high melting points b.) have high boiling points c.) do not dissolve well in water d.) conduct electricity
c.) do not dissolve well in water
Substituted hydrocarbons include all of the following EXCEPT _________. a.) alcohols b.) halogen compounds c.) minerals d.) organic acids
c.) minerals
Carbon is a common component of which of the following items? a.) air b.) iron c.) people d.) water
c.) people