1. Basic Chemistry Vocabulary Standard Biology Zito/Farrell SY 2009-2010

2. Atom the smallest component of an element having the chemical properties of the element made up of a specific arrangement of protons, neutrons, and electrons

3. Nucleus positively charged, dense center of an atom contains the protons and the neutrons

4. Proton a particle of an atom with a positive charge of +1 and a mass of 1 unit always found in the nucleus of the atom An atom of a specific element ALWAYS has the same number of protons. If you change the number of protons, you make a DIFFERENT element.

5. Neutron a particle of an atom with a neutral charge (charge of 0) and a mass of 1 unit always found in the nucleus of the atom An atom can have different numbers of neutrons. If you change the number of neutrons, you make a heavier or lighter ISOTOPE of the SAME element.

6. Electron a particle of an atom with a negative charge of -1 and a mass of 0 units always outside of the nucleus of the atom Electrons live in layers called clouds or orbitals. An atom of an element can have different numbers of electrons. (more on the next slide)

7. Electrons – ion formation Atoms with the SAME number of protons and electrons are called stable atoms, or just plain old atoms. An atom that loses or gains electrons is called an ION. Losing electrons makes a positive ion (cation) Gaining electrons makes a negative ion (anion)

9. Molecule One or more atoms bonded together Each molecule that exists has a certain number of atoms, bonded together in a specific arrangement

10. Molecule Examples Oxygen is O 2 and looks like this. Ex: Glucose is always C 6 H 12 O 6 and looks like this:

11. Compound Some molecules are compounds, some are not. A compound has at least two kinds of atoms. Sugar has C, H, & O. it is a compound. Oxygen only has O atoms. It’s not a compound. (But it is still a molecule.)

12. Bonds Bonds Between atoms 1 Electrons are the part of the atom involved in bonding. Sometimes one atom totally gives up an electron and another one takes it. This is Ionic Bonding (because ions are made).

13. Bonds Between atoms 2 Electrons are the part of the atom involved in bonding. Sometimes two atoms share an electron. This makes a COVALENT bond (because they are CO-operating).

14. Physical Changes anything that does not change the chemical structure of the molecules (basically, anything that makes it get bigger, get smaller, or change shape) Freezing, melting, evaporating, condensing, crushing, stacking, increasing, dissolving…

15. Chemical Changes anything that changes what you have into something else (difficult or impossible to reverse) Ex: Burning paper (C 6 H 12 O 6 )n + O 2 = C + H 2 O = CO 2 Paper + Oxygen turn into Water, Carbon Dioxide, and Carbon dust.

17. Mixture two or more substances mixed together - not in fixed proportions - not chemically bonded together - can be separated *Blood is a mixture.

18. Solution a homogeneous (evenly combined) mixture of two or more substances *frequently (but not necessarily) a liquid Ex: sugar water Solute – the part that dissolves (sugar) Solvent – The part that it dissolves into (water)