Physical Science - Chapter 6

What event changed scientists’ thinking about organic compounds and chemistry?

Friedrich Wöhler accidentally made the organic compound urea, which meant that man could produce organic compounds.

Name three characteristics of carbon atoms that allow them to form so many different organic compounds.

Since carbon has four valence electrons, it can bond with up to four different atoms. When carbon atoms bond with each other, they form very strong, durable bonds. Carbon’s four valence electrons also enable them to form single, double, and triple bonds.

What are hydrocarbons?

molecules that contain only carbon and hydrogen atoms.

Why is the term straight chain somewhat misleading?

The term suggests that the chain always forms a straight line, but straight chains can have bends and turns in them. They are straight in the sense that there is one path of carbon atoms from end to end.

What are isomers?

molecules with the same molecular formula but with a different arrangement of atoms.

Compare alkanes, alkenes, and alkynes. All three are hydrocarbons.

Alkanes are saturated, while alkenes and alkynes are unsaturated. Alkanes have only single bonds between carbon atoms, alkenes have at least one double bond, and alkynes have at least one triple bond.

Why is butyne much more reactive than butane?

It has a triple bond.

What changes the properties of hydrocarbons?

By altering its composition, internal structure, or both.

How do substituted hydrocarbons differ from hydrocarbons?

Substituted hydrocarbons are formed by replacing a hydrogen atom with an atom of another element or with a group of atoms.

What is a hydroxyl group, and what is its relationship to alcohols?

a hydrogen atom bonded to an oxygen atom. It is the functional group of alcohols.

What is a carbonyl group? In which group(s) of substituted hydrocarbons would you find one?

A carbonyl group is a carbon atom bonded with an oxygen atom in a double bond. It is the functional group in ketones and aldehydes.

Name two uses of alcohols.

They are commonly used as solvents, in detergents, and as fuel additives.

Explain how monomers and polymers are related.

Polymers are massive molecules formed from linking smaller molecules called monomers.

Explain how starches and sugars are related.

Starches and sugars are both carbohydrates. Starches are polymers made from the linking of sugar molecules.

How do plants, animals, and humans use starches?

Plants produce starches from glucose and use it to store energy. Animals and humans use starch as a source of energy.

Evaluate the statement, “For a healthy diet, we must avoid eating fats.”

This statement is false. Fats help many cellular functions as well as brain function

Compare the structure and function of RNA and DNA.

RNA and DNA are both nucleic acids. They differ in the composition of their nucleotides. RNA has a ribose as the sugar in its nucleotide, while DNA has a ribose-derived sugar— deoxyribose—as its sugar. RNA functions in protein synthesis, while DNA contains the genetic information that governs the growth, function, and reproduction of cells.

What are carbohydrates made of?

chains of sugars

What do carbohydrates and lipids due for the body?

gives it energy

What are lipids made of?

chains of carbon & hydrogen atoms

What foods contain lipids?

oil and lards

What are proteins made of?

chains of amino acids

What does protein due for the body?

it builds body structure

Give two examples of synthetic polymers and how we use them.

polyethylene for water bottles and food containers, nylon as a silk and cotton replacement, Nomex in flame-resistant clothing, and Twaron in ballistic resistant clothing.

What biochemical macromolecules do our bodies use?

carbohydrates, proteins, and lipids

What monomers link to form proteins?

amino acids

What are good food sources of proteins?

meats, eggs, beans, peanuts, tree nuts, and legumes.

What are lipids?

polymers made from carbon, hydrogen, and oxygen. We know them as fats, oils, waxes, and cholesterol.

What are nucleic acids?

polymers made from nucleotides. They encode, store, and provide instructions for processes in all living cells.