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Intro to Chemistry
Introduction to Chemistry
Question | Answer |
---|---|
atom | The smallest unit of matter. This cannot be divided any smaller. |
Proton | Particles with a positive charge. |
Electron | Particles with a negative charge. |
Neutron | Particles that do NOT have a charge. |
Element | A substance that is made up of one kind of atom. |
Molecule | Is made up of 2 or more atoms held together by bonds. Example: CO2, NaCl, O2, H2 |
Periodic Table of Elements | A chart showing all the known elements on Earth; these are arranged in groups that share certain characteristics. |
Atomic Number | Tells the number of protons in the nucleus of an atom. It can also be used to determine the number of electrons. |
Atomic Mass | Total mass of an atom includes protons, electrons & neutrons. |
Chemical Properties | Can be observed when an element is chemically changed. Examples: flammability, how easily it rusts. |
Physical Properties | Can be observed or measured without changing the element. Examples: color, mass, density. |
Compound | Made up of two or more elements that are chemically combined. Examples CO2 or Glucose (C6H12O6) |
Mixtures | Contains 2 or more substances that are physically combined but can be separated easily. |
Bond | Something that connects or joins atoms together - happens through the interaction of electrons. |
Chemical Formula | A combination of elements and how many elements there are. For example, CO2 has 1 carbon and 2 oxygen. |
Chemical Equations | Shows the starting reactants and the end products. Example: H2O + CO2+Sunlight ------> C6H12O6 + O2 |
Chemical Reactions | A process that changes, or transforms one set of chemicals into another set of chemicals. |
Reactants | The "ingredients" necessary for a chemical reaction. |
Products | What is created or produced after a chemical reaction. |
Law of Conservation of Mass | Mass can NOT be created or destroyed. |