Chapter 3-4 Flashcards
Physical Change:
Changes where the fundamental entities remain unchanged at a molecular level. There is no change in the written formula of the substance and involves a small amount of energy change. (State/energy change, no new substance)
Chemical change:
Change in the chemical bonding of the fundamental entities of a substance and represented by a change in the written formula. A new substance is formed with physical and chemical properties different than those of the original matter. Chemical changes involve larger energy changes. (color, odor, state and/or energy change, a new substance, new permanent properties, medium energy change.)
Nuclear Change:
Changes within the nucleus which create entirely new atomic entities. These entities are represented by formulas that show new atomic symbols, different from those of the original matter. Involves extremely large changes in energy, which allow them to be identified. (Radiation often emitted, new elements formed, enormous energy change)
Kinetic energy:
A form of energy related to motion.
Kinetic Molecular Theory:
The idea that the smallest entities of a substance - atoms, ions, or molecules - are in continuous motion, colliding with each other and objects in their path.
Explaining chemical reactions:
According to kinetic molecular theory, if different substances are present, different entities would collide with each other and if the collision has a certain orientation and sufficient energy, the components of the entities will rearrange to form new entities, which is the chemical reaction. (This is the colllision-reaction theory)
Diagnostic test:
A short laboratory procedure with expected evidence and analysis.
Amount of substance/chemical amount:
SI quantity for the number of entities in a substance, measured in units of moles (mol): Measured in SI symbol, mol.
Avagadro’s number/constant:
The number of entities of a chemical; substance in mole of that substance: 6.02x10^23/mol
