click below
click below
Normal Size Small Size show me how
Definitions CH 6
Exam 3
Question | Answer |
---|---|
Physical change | the chemical composition of the substance is the same. Ex melting ice, boiling water |
Chemical change | the chemical composition of the substance changes. There is a chemical reaction that makes a new substance |
Chemical compounds of fireworks (ions or ionic compounds) | Na (orange-yellow), Ba (green-yellow), Ca (red-orange), Sr (bright red), Li (scarlet red), Cu (blue-green), Al & Mg (white sparks) |
Four observations of a chemical reaction | Gas release (fizzing or bubbling) Insoluble solid (ppt)that forms from 2 aq sol Permanent color change (new substance) Heat energy change (Ex. heat and light ) |
Aqueous solution | Substance dissolved in water |
Precipitate (ppt) | insoluble solid formed after adding 2 aqueous solutions together |
Exothermic reaction | Reaction that releases heat |
Endothermic reaction | Reaction that absorbs heat |
Chemical equation | description of a chemical reaction using formulas and symbols |
Reactants | A + B - |
Products | - C + D |
Catalyst | Speeds up the reaction without being comsumed (above the arrow) |
7 Diatomic Molecules | H, Ni, O F, Cl, Br, I |
Balance chemical equation | the number of atoms of each element is the same on both sides of the arrow |
Coefficient | Whole # in front of each substance used to balance chemical reactions. |