Term | Definition |
A molecule | is a group of two or more atoms linked together by chemical bonds. |
Weight | is the measure of the force of gravity upon an object |
Density refers | to the ratio of an object's mass to it's volume |
Density | color and molar mass are all physical properties. |
Accuracy | is how closely a measured value matches the actual value. |
Atoms | are the smallest particles into which an element may be broken down without changing the identity. |
Liquid | is the state of matter where particles have enough energy to move freely but not enough energy to overcome there attraction for each other. |
Atomic number | is the number of protons in an atom. |
Molar mass | is the mass per mole of a substance; usually given in grams per mole. |
Nucleus | the dense central portion of an atom |
Hypothesizing | the step of the scientific method that would involve thinking about nature to develop an idea about how something works |
Electrons | the negatively charged subatomic particles in an atom |
Density | the quantity of the ratio of mass to volume |
Diffusion | the molecular process that would cause a dye and water to mix |
Electron | a subatomic particle that is not found in the nucleus of an atom |
John Dalton | developed the atomic theory of matter |
Molecules | the smallest particles into which a compound may be broken down without changing it into another substance |
Distillation | the general term for techniques of separating liquids based on their boiling points |
Combination reaction | a reaction in which two (or more) substances chemically combine to form one new substance |
Decomposition reaction | The reverse of combination. It involves the breakdown of a single reactant compound into two or more simple substances, either elements of compounds |
Single-displacement reactions | also called single-replacement, substitution, or displacement reactions, involves replacing one element in a compound with another |
Double-displacement reactions | happens when positive and negative parts of tow ionic compounds are inter changed. They are easily recognized since there are two compounds on either side of the arrow |
Barometer | used to measure atmospheric pressure |
Physical chemistry | fundamental to the other areas of chemistry, and deals with applying the theories of physics to the study of reactions and properties of matter |
Organic chemistry | deals with the study of substances that are compounds of carbons |
Inorganic chemistry | deals with substances that are chemical combinations of elements other than carbon. |
Bio-chemistry | the chemistry of living things. |
Analytical chemistry | deals with identifying what substances are present in materials and how much of each substance is present |
Mole | the unit equivalent to Avagadro's number of objects |
Molecular mass | the sum of the atomic masses of all atoms in a molecule |
Atomic number | the number of protons in an atom |
Ion | The name given to an atom or molecule when they have a different number of electrons than protons |
Anion | An ion with more electrons than protons and has an excess of positive charges. A negatively charged ion |
Cation | An ion with fewer electrons than protons and has an excess of positive charges. A positively charged ion |
Isotopes | atoms of the same element that differ in their mass numbers |
Molecular compounds | compounds composed of molecules |
Ionic compounds | compounds of a vast array of ions |
Molecular formulas | tell how many of each type of atom are found in an actual molecule of that substance |
Empirical formulas | show only the simplest ratio of atoms in a compound |
Name of an ionic compound | consists of the name of the cation followed by the name of the anion |
Law of Definite Compostition | states that a given compound will always have the same mass ration or mass percent, no matter what it's origin. |
Reactants | substances that react and are written on the left of a chemical equation |
Substances | produced in the reaction and are known as products, and are written on the right of a chemical equation |
The Law of Conservation of Mass | states that the sum of the masses of the products is always equal to the sum of the masses of the reactants |
Chemical reactions | chemical changes caused by collisions between atoms and molecules |
Plasma | a hot gas in which atoms are partially broken down to form charged particles, or ions. Plasma is the only state in which matter may exist, It is the fourth state of matter |
Solid | has a definite shape and volume. It is a state of matter |
Liquid | particles that have enough kinetic energy to break loose from their rigid positions. Attraction still keeps the particles of matter very close together, however they can slip and slide freely over each other. It is a state of matter |
Gas | does not have a definite shape or volume an is easily compressed. It is formed when liquid is heated to the boiling point and the particles gain enough kinetic energy to break away from each other, It is a state of matter |
Compound | a substance that can be decomposed by chemical means into simpler substances |
Pure substances | have a definite composition; that is, the relative amounts of each element in a given compound are unchangeable, no matter where the compound may be found. They are also homogeneous |
Homogeneous | composed of the same kind of matter throughout a sample |
Mixture | a substance consisting of two or more pure substances that are physically mixed but not chemically combines |
Heterogeneous mixture | consists of pure substances that are incompletely mixed |
Electrons | negatively charged particles |
Neutrons | neutral particles |
Matter | anything that occupies space and has mass |