| A | B |
|---|
| What are atoms composed of? | protons, neutrons and electrons |
| what is the smallest particle of matter? | an atom |
| What does a carbon atom retain? | all chemical properties of carbon. |
| What substance is composed of only one type of atom? | an element |
| what is all matter in the universe composed of? | atoms |
| Where are the electrons in an atom? | they orbit the nucleus in various energy levels |
| What is the bond called when two atoms share a pair of electrons? | a covalent bond |
| What is an ion? | an atom that has gained or lost electrons |
| What is an ionic bond? | a bond formed when electrons are exchanged between atoms |
| When must a reaction involve the release of energy? | When the products of a chemical reaction contain less energy than the reactants |
| What drives all the activities occurring within cells? | Chemical reactions |
| What are enzymes? | biological catalysts |
| What does a neutral solution contain? | an equal number of hydroxide and hydronium ions |
| What do the terms base and alkaline refer to? | solutions that contain more hydroxide ions than hydronium ions |
| What is the pH of bases? | 8-14 |
| What is the pH of acids? | 1-6 |
| What do buffers do? | tend to prevent great fluctuations in pH |
| What molecules have no negative or positive poles. | Nonpolar molecules |
| Why is water important to life? | It surrounds and found inside cells and shapes membranes |
| Why is water a polar molecule? | Different parts of the molecule have slightly different charges |
| What do all organic compounds contain? | C - carbon |
| What organic molecule is classified a carbohydrate? | sugar |
| What are polysaccharides? | carbohydrates |
| What kind of monomers are amino acids? | proteins |
| What are found in proteins? | long chains of amino acids |
| What is an example of nonpolar molecules? | lipids |
| What are lipids soluble in? | water, salt water and oil |
