Chem Basics CHAP 2 Flashcards
Matter
Matter
anything that has mass and takes up space - either an element, compound or mixture
NOT light or sound
Element
A substance that can’t be separated/broken down into simple substances by chemical means (Carbon, Copper)
Atom
smallest unit of an element that maintains its (element’s) chemical properties
Molecule
group of atoms held together by chemical forces
smallest unit of matter that can exist by itself and still maintain a substance’s chem properties
Compound
a substance made of atoms of two or more different elements joined by chemical bonds (Water, for example)
3C12H22O11 - Table Sugar; Explain each Component
Chemical Formula
Subscripts (12, 22, 11) are the # of ATOMS
3 = the # of MOLECULES (3 in front/preceding #)
Letters = Element Abbreviations
Chemical Formula
Shows how many atoms of each element are in a unit of a substance.
Pure Substance
Matter (a single compound or element) that has a fixed composition and definite properties
Mixture
two or more substances combined that are NOT chemically combined
Which is NOT a pure substance?
Elements, Compounds, Mixtures
Mixtures - can be physically separated into its parts
Pure Substances are CHEMICALLY combined
Heterogenous Mixture
A mixture where its parts/substances are NOT evenly distributed (salad, a shirt)
Homogenous Mixture
A mixture where its parts/substances ARE evenly distributed (vinegar, gasoline)
Miscible
able to be mixed
Immiscible
unable to be mixed (oil + water)
___ ___ are characteristics that can be observed without changing the identity of the substance.
Physical properties.
color, mass, shape, volume, texture, odor, STATE
strength, hardness, magnetism
heat or electricity conduction
3 States of Matter:
Solid, liquid, gas
The temperature at which a substance changes from solid to liquid.
Melting Point
The temperature at which a substance changes from liquid to gas.
Boiling Point
ANY ___ ___ has constant boiling and melting points if the pressure remains the same.
PURE SUBSTANCE
The ratio of the mass of a substance to its volume is what?
Hint: physical property
DENSITY
D = m/V or Mass/Volume
How does Weight differ from Density?
Weight can be equal regardless off volume.
1lb of feathers vs. 1lb of steel WEIGH the same
but the steel is still more DENSE regardless (more mass per unit of volume)
___ ___ describes how a substance changes into a new substance, either by combining with other elements or by breaking apart into new substances,
Chemical Properties
Ex: flammability, reactivity, corrosion, acidity, toxicity, Heat of Combustion, Oxidation State, Chemical Stability (level of resistance to chemical change or reaction)
Reactivity
the capacity of a substance to combine chemically with another substance
how nicely they do they play with others? :)
