SCIENTIFIC INVESTIGATIONSA ___________________ is an explanation that might be true and can be tested.
HypothesisThe factor that is changed in the experimental group is the _____ variable. It is plotted on the x-axis.
Independent
SCIENTIFIC INVESTIGATIONSWhat you measure in an experiment is called the ________________ variable. It is plotted on the y-axis.
DependentName 3 good safety rules for a Chemistry lab.
UNIT 1 – SCIENTIFIC MEASUREMENT
Write the following numbers in scientific notation.
52, 300 5.23 x 104
0.0353.5 x 10-2
UNIT 1 – SCIENTIFIC MEASUREMENT
The measure of how close a measurement is to what it should be is called the ____
AccuracyThe repeatability of a measurement is called ____
Precision
UNIT 1 – SCIENTIFIC MEASUREMENT
I conduct an experiment and measure the mass of a substance as 7.31 g. The accepted value is 7.5 g. What is the percent error?
(7.5-7.31) / 7.5 x 1002.5%
2009 SOL QUESTIONA student determined that the
density of a sample of tin is 8.00 g/mL, when the actual density is 7.28 g/mL. What is the percent error?
F 0.72%G 9.0%H 9.9%J 91%
UNIT 1 – SCIENTIFIC MEASUREMENT
How many significant figures are in each of the following numbers?2.030.0086078,00050014.0 x 104
2009 SOL QUESTIONA compound has a mass of 2.6632 x 102 g/mol. The number of sig figs in this mass is –
F 2G 4H 5J 7
UNIT 1 – SCIENTIFIC MEASUREMENTWhen measuring volume with a
graduated cylinder, be sure to measure at the bottom of the ________________
MeniscusWhen measuring temperature, do not
allow the thermometer to touch the _______________ of a beaker or other container.
Bottom or sidesMass is typically measured in _________Grams
2009 SOL QUESTIONWhen 1 g of NaCl is placed in 100g of water, a solution results. Once the solution is prepared, water is now considered what part of the solution?
F SoluteG Solvent
UNIT 13 – EVERYTHING ELSEVaporization is an _____ process. EndothermicFreezing is an ______process. ExothermicHeat (q) is the ________ of energy between objects at different temperatures.
Transfer
UNIT 13 – EVERYTHING ELSEHeat is an ________ property --- it depends on the amount of the substance present.
ExtensiveThe total energy content of a sample is called its __________.
Enthalpy
UNIT 13 – EVERYTHING ELSEThe measure of disorder or
randomness in a system is called the ______________________.
EntropyA catalyst is a substance that speeds
up the reaction by ___ the activation energy.
Lowering Increasing the temperature,
concentration, pressure, or surface area of a substance will ______ the reaction rate.
Increase
UNIT 13 – EVERYTHING ELSEWhen the forward and reverse
reactions happen at the same rate, it is called ___
Chemical equilibriumGive an example of a completion
reaction.Le Chatelier’s principle states that
when a system is at equilibrium is disturbed, the system adjusts in a way to ______________ the change.
Reduce
UNIT 13 – EVERYTHING ELSEIncreasing the concentration of
the reactants will make the ______ reaction faster than the reverse.
Forward This is called a shift __________.Right An oxidation reaction is one in
which electrons are __________.Lost