Question | Answer |
Atom | Smallest possible unit of an element that retains the physical and chemical properties of its element |
Matter | occupies space and has mass |
Ion | charged atom or molecule |
Element | a substance that can't be broken down into simpler substances by chemical reactions |
Compound | molecules made from more than one type of atom |
Isotope | atoms of an element that have the same atomic number but different mass number |
Molecule | atoms that have combined chemically |
Atoms vs. elements | atoms:smallest amount that makes up elements
elements: Basic substance that can't be simplified |
Molecule vs. compounds | not all compounds are molecules but all molecules are compounds |
Formation of an ion | ion is an atom or molecule that has lost or has gained
one or more valence electrons |
Isotopes of various elements | they have the same atomic number, but different mass |
Polar covalent bond | covalent bond formed by an unequal sharing of electrons between atoms |
Non-polar covalent bond | covalent bond formed by an equal sharing of electrons between atoms |
Ionic bond | Bond formed by the electrostatic attraction after the complete transfer of an electron from a donor atom to an acceptor |
Proton, Neutron, and Electron | Neutron= no charge
Proton= +1
Electron= -1 |
pH scale differences basic, acidic, neutral | In a neutral solution, [H+] = 10-7 M and [OH-] = 10-7 M.
In an acidic solution where the [H+] = 10-5 M, the [OH-] = 10-9 M.
In a basic solution where the [H+] = 10-9 M, the [OH-] = 10-5 M. |
What is a pH scale? | pH scale is a scale used to measure degree of acidity. It ranges from 0 to 14. |
pH level in the environment increases or decreases | Increase and decrease:substance that minimizes large sudden changes in pH. |
Examples in which organisms resist pH to maintain homeostasis | Work by accepting H+ ions from solution when they are in excess and by donating H+ ions to the solution when they have been depleted. |