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Physical Science


substance that cannot be chemically broken down into simpler substances


substance made up of two or more elements that are chemically combined


two or more substances that have been physically combined


any element or compound


smallest part of any substance that has all the properties of that substance

chemical bond

force of attraction that holds atoms together

valance electron

electron in the outermost energy level of an atom


atom with an electrical charge

ionic bond

bond formed between atoms that have gained or lost electrons

covalent bonds

bond formed when atoms share electrons

organic compound

compound containing carbon

organic chemistry

study of organic compounds

structural formula

molecular model that uses straight lines to indicate bonds


large molecules that are formed by many smaller molecules


sugars and starches


fats and oils


compounds used to build and repair body tissues

amino acids

building blocks of proteins

nucleic acids

compounds made up of carbon, oxygen, hydrogen, nitrogen, and phosphorus

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