Chapter 1 Matter, Measurements & Problem Solving Flashcards
molecules
atoms that bond together
ex: CO2
Chemistry
understanding the behavior of matter by studying the behavior of atoms and molecules
Empirical
based on observation and experiments
Qualitative
describing how and experiment happens
Quantitative
measuring the data
Hypothesis
tentative interpreation/ explanation of observation
-falsifiable: confirmed or refuted
Experiments
highly controlled procedures designed to generate observations that can confirm/deny hypothesis
scientific law
brief statement that summarizes past observations & predicts future ones
Law of Conservation of Mass
Matter is neither created nor destroyed
Scientific theory
model for the way nature is and tries to explain not merely what matter does
Atomic Theory: (Dalton)
Matter is composed of small indestructible particles called atoms
Matter
Anything that occupies space and has mass
Substance
State, composition (s,l,g)
Solid
atoms/molecules pack tightly together in fixed formation/location.
*fixed V rigid shape
- Crystaline: arranged in patterns w/ long range repeating order
- Amorphous: don’t have any long range pattern
Liquid:
pk closely together, free to move around relative to one another
- fixed V no shape
- assume shape of container
Gas
Lots of space between
- compressible
- assume V and shape of container
composition
kinds/amount of substances the compose it
pure substance
composed of a single time of atom/molecule
mixture
composed of 2 or more different types of atoms/molecules
element
can not be chemically broken down into another substance
Compound
2 or more elements in fixed, definite proportions
heterogenous mixture
composition varies between on region to another
homogenous mixture
same composition throughout
physical change
alter only state/ appearance
-NOT composition
EX water boiling
chemical change
alter composition
EX iron rusting
physical property
displays w/o changing composition
-smell
chemical property
only changing composition via chemical change
-flammability
Kinetic Energy
associated with motion
-total energy of an object
Potential Energy
energy associated with position/ composition
Thermal Energy
energy associated w/ temp of object
Law of conservation of energy
energy is neither created nor destroyed
Units
standard quantities used to specify measurement
Meter (m): length
Kilogram (kg): mass
Second (s): time
Kelvin (K), Farenheit (F) Celsius (C): temp (Kelvin - standard)
Volume
Measurement of space
- Liters (L) or milimeters (mL)
Density
ratio of mass to volume
d=m/v
intensive property
independent from amount of substance
- density
extensive property
depends on amount of substance
-mass
Significant Figures
Greater the # of sig figs the greater the accuracy
1. all nonzeros = sig
2. interior zeros= sig
3. leading zeros= NOT sig, only place holders
4. trailing zeros:
after dec point= sig
before dec point but after non zero= sig
before implied dec pt= ambiguous
use scientific notation
Exact numbers
- no uncertainty, dont limit # of sig figs
- 100cm= 1m
- unlimited number of sig figs
Random Error
equal probability of being too high/low
systematic error
error tends towards too high/ too low
Dimensional Analysis
using units as guide
conversion factor
converting from = on bottom
converting to = on top
Atoms
Subatomic particles that constitute fundamental building blocks of ordinary matter
*free atoms = rare in nature
