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Periodic Table | A chart of the chemical elements, arranged by grouping elements with similar properties. |
Physical properties | Characteristics of a substance that can be tested and/or observed. |
Reactants | Substances that may undergo a chemical change in an experiment. |
Meniscus | The curvature in a liquid noticed inside a graduated cylinder. We use the bottom of it to measure accurately. |
Chemical change | A reaction that creates a new substance. Evidenced by color change, making heat, gas, or a soild |
Precipiate | A new solid that is formed from a chemical reaction. |
Physical Change | When s substance changes size, shape, or phase but is STILL the original substances. |
Particle | A very small piece of matter, such as an atom. |
Matter | Anything that contains mass and takes up space. |
Element | A group of substances that cannot be separated into simpler substances by chemical means. |
Compound | A pure substances composed of 2 or more elements. |
Conservation of Mass | Rule that states that in a closed system, even after physical and chemical changes occur, the total amount of the substances you started with equals the total amount of the substances you end with. |
Dichotomous Key | A tool used to categorize substances by asking questions that have only two choices. |
Open system | An experimental set-up in which mass or energy can be lost or gained from its surroundings enviroment. |
Solid | The phase of matter that has a definite shape and volume. |
Closed system | When reactions take place without the influence of outside factors. Nothing is lost or gained. |
Liquid | The phase of matter where the atoms take the shape of its container. |
Acid | A substances with a pH less than 7, has a sour taste and keeps or turns litmus paper pink. |
Gas | The phase of matter where the atoms fill the shape and volume of its container. |
Base | A substance with a pH greater than 7, feels slippery, tastes, bitter, and keeps or turns litmus paper blue. |
Solubillty | Capable of being dissolved or liquefied. |
Atom | Smallest part of any substance that contains protons, neutrons, and electrons. |
Melting point | Temperature at which a substance changes from a solid to a liquid. For water it is 0 celsius. |
Litmus paper | An indicator tool, made of paper, that changes colors in the presence of acid or a base. |
Boiling point | Temperature at which a substabce changes from a liguid to a gas. For water it is 100 celsius. |
Neutral | Term used for a substance whose pH is 7, water is an example. |
Mixture | a combination of materials that can be separated by physical means. |
pH | a way of expressing how acidic or basic a substance is on a scale or 0-14. |
Pure Substances | Any single type of matter that cannot be separated by physical means. |
Blue | This color on litmus paper indicates a base. |
Freezing point | Temperature at which a substance changes from a liquid to a solid. For water it is 0 Celsius. |
Red/pink | This color on litmus paper indicates an Acid. |
Polymer | A long molecule of a chain of smaller, simpler molecules. |
Exothermic | A chemical reaction which releases heat. |