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Chem Part 2
Acids & Bases, Density, Atmosphere, Products & Reactants, and Law of Con of Mass
Question | Answer |
---|---|
What is an acid? | any compound that increases the number of hydrogen ions when dissolved in water |
What is a base? | any compound that increases the number of hydroxide ions when dissolved in water |
What is a chemical bond? | an interaction that holds atoms or ions together |
What is chemical bonding? | the combining of atoms to form molecules or compounds |
What is a chemical change? | a change that occurs when one or more substances changes into a new substance with different properties |
What is a chemical formula? | a combination of chemical symbols and numbers to represent a substance |
What is a a chemical reaction? | the process by which one or more substances change to produce one or more different substances |
What is a compound? | a substance made up of atoms of two or more different elements joined by chemical bonds |
What is density? | the ratio of the mass of a substance to the volume of the substance, how tightly compacted the particles of an object are, Density = mass/volume |
What is an indicator? | A compound that can reversibly change color depending on conditions such as pH |
What is an ion? | a charged particle that forms when an atom or group of atoms gains or loses one or more electrons |
What does the Law of Conservation of Mass state? | Mass cannot be created or destroyed but can change forms. The amount of mass that goes into a chemical reaction = the amount at the end of the reaction. |
What is mass, the tool used to measure mass, and the unit? | Mass is the amount of matter in an object. The tool used to measure mass is the triple-beam balance. The unit is grams. |
What is matter? | Anything that has mass and takes up space. |
What is a molecule? | The smallest unit of a substance that keeps all of the physical and chemical properties of that substance |
What is pH? | a value that is used to express the acidity or basicity (alkalinity) of a system |
What is a product? | A substance that forms in a chemical reaction, the results - products are on the right side of the chemical equation |
What is a reactant? | a substance that participates in a chemical reaction , the ingredients - reactants are on the left side of the chemical equation |
What is a closed system? | It is a system in which neither reactants nor products can enter or escape |
What is the pH range for acids and what number is the most acidic? | 0-6.9 0 is the most acidic and 6.9 is the least acidic. |
What is the pH of pure water? | 7 - it is neutral |
What is the pH range for bases? What number is the most basic? | 7.1-14 14 is the most basic and 7.1 is the least basic. |
What are some common properties of acids? | tastes sour, conducts electricity, corrosive,reacts with metals, pH of 0-6.9 |
What are some common properties of bases? | tastes bitter, feels slippery to touch, can conduct electricity, pH of 7.1-14 |
What are the most abundant gases in Earth's atmosphere? | Nitrogen - 78%, Oxygen - 21%, Argon - 0.9%, Others - 0.1% |
What are the reactants that form rust? | Oxygen AND Iron. Water is NOT involved. |
What color does an acid turn litmus paper? | An acid turns blue litmus paper red. |
What color does a base turn litmus paper? | A base turns red litmus paper blue. |