test 1 Flashcards
dimensional analysis
changing quantities by units of measure mkhddcmmnp
heterogenous mixture
Each component keeps its original properties each sample of the mixture will be different not uniform
homogenous mixture
completely uniform in composition and portion of components each sample of the mixture is exactly the same
chemical change
when matter undergoes changes in composition
physical change
alter a substance without changing its composition
mixture
A physical blend of two or more substances which retain their own identity
compound
combination of two or more atoms can be separated chemically
solution
homogeneous or heterogeneous a combining of 2 or more different substances
atomos
indivisible
smallest particle
atom
atomic theory
- all elements are composed of indivisible particles called atoms
- All atoms of the same element are identical in properties
- Atoms cannot be created or destroyed or subdivided by any chemical reaction
- Atoms of different elements can physically mixer chemically combine in simple whole number ratios to form chemical compounds
-  Chemical reactions can occur when atoms are separated join or rearranged
what part of the atomic theory is wrong
that atoms cannot be divided because they are made of electrons neutrons and protons
law of conservation mass
atoms cannot be created or destroyed during chemical or physical changes
problem with bohrs solar system model
The electrons are not being moved around the nucleus in constant speeds because they would implode
quantum mechanical model
based on the solar system model electron stay in the spot in the space between the nucleus they don’t move called the electron cloud model