Science Quiz #1 Flashcards
Mixture
A mixture is made of two or more substances together in the same place but their atoms are NOT chemically combined.
Heterogenous Mixture
A type of mixture with distinct materials that can be easily seen and sorted
Homogeneous Mixture
A type of mixture with materials that are hard to see an sort
Examples of how particles are separated
Size, filters, magnets, and evaporation
Colloid
A heterogeneous mixture containing small, undissolved particles that do not separate or settle out if the mixture is left undisturbed
Suspension
A mixture with particles that can be seen and easily separated by settling of filtration.
Solutions
A homogeneous mixture of a solvent and one or more solutes
Solvent
The part of the solution that is usually present in the largest amount.
Solute
The substance that is dissolved by the solvent
Molecular solutes
A molecule or particle that is distributed in a solvent
ionic Solutes
electrolytes and nonionic solutes are nonelectrolytes
Examples of physical properties
Boiling point, Freezing point, and density
Solubility
A measure of how much solute will dissolve in the solvent.
Effect of Temperature
The higher the temperature the faster the molecules move.
What is an example of both Physical and Chemical Changes
Cooking
Physical Change
A change that alters the physical form or appearance of a substance without changing it into a different substance
Examples of Physical change
Bending, Crushing, Cutting, Melting, Freezing, and Boiling
Chemical Changes
A chemical change is a change in matter that produces one or more new substances
Reactants
Substances that undergo Chemical Changes
Products
What reactants form
Examples of Chemical Change
Burning and rusting
When do chemical changes occur
When existing bonds break and form new bonds.
Signs that a chemical reaction has occurred
Changes in energy and changes in properties.
Examples of Properties changing
Change in color, Gas Production, Formation of Precipitate
Precipitate
When a liquid turning into a solid
Exothermic Reaction
A reaction that releases energy, usually in the form of heat.
Endothermic Reaction
A reaction that absorbs energy
Activation Energy
The minimal amount of energy needed to start a chemical reaction
What might affect the rate of a chemical change
Surface area, temperature.
Cutting paper
Physical
Ice mealting
Physical
Toast Burning
Chemical
Rocket fuel burning
Chemical
Sawing wood
Physical
Metal rusting
Chemical
Disappearing Puddle
physical
Candle burning
Chemical
Dry ice
Physical
