Test 1 Flashcards
Precision
All in one area
Accuracy
Close to bullseye
Theory
Something you can’t prove
Law
Happens all the time in nature
of sig figs 008.0030
5
of sig figs in 0.00800
3
of sig figs in 5000? What about 5000.?
0, 4
Matter
All physical material in the universe
Atoms are usually found in a ______ State
Combined
Molecules can be
Two of the same atoms or two different atoms
Elements are the
Building blocks of matter
A pure substance
Cannot be separated into simpler substances by physical means
Has definite and constant chemical+physical properties
Example of definite chemical+physical properties
Melting/boiling points
A pure ELEMENT is
A pure substance that consists of only one type of ATOM
Pure COMPOUND is
A pure substance that has MORE THAN ONE TYPE of atom
Allotropes are?
Elements which have a different number of atoms in the molecule. They have different chemical and physical properties
Individual elements and compounds are all _____
Pure
Is NaCl pure?
Yes
Is NaCl+H2O pure?
No it has two compounds
6 main elements in the human body?
CHNOPS
When a substance goes through a ______ change, its physical appearance changes, but its chemical nature does not
Physical
When a substance changes it’s composition, it undergoes a ____ change
Chemical
Kelvin Scale
Same increment as Celsius
Absolute zero is -273.15°C
Celsius
Water freezes at 0°
Boils at 100°
