chemistry
how many significant figures are in the number 124.10?
5
how many sig figs are in the number 540, 962.17?
8
freezing point of water in celcius
10
what is the boiling point of water in celcius
100
boiling point of water in fahrenheit
212
what is freezing point of water in fahrenheit
32
how many sig figs are in the number 0.0001234?
4
which of the following is NOT a state of matter
density
this depends on the independent variable
dependent variable
this is put on the y-axis when graphing
dependent variable
a technique that uses the differences in boiling points to separate a liquid homogeneous mixture is
distillation
a material that cannot be broken down further by chemical means is an
element
type of colloid in which liquids that normally don't mix are spread throughout each other
emulsion
properties that depend upon the amount of substance present and have to be a "number" are
extensive properties
the mass of the football is 3.3 kilograms. this is an example of a
extensive property
collecting data from a line that goes BEYOND the plotted points on your graph is called this. it's really easy to make errors doing this
extrapolation
a technique that uses a porous barrier (like a strainer) to separate heterogeneous mixtures is
filtration
a __ is a form of matter that has a definite shape, and a definite volume
solid
sublimation is a process in which a __ changes to a __ without melting
solid, gas
substance that dissolves into a __ to form a solution
solute, solvent
which of the following is a vapor
steam
force acting on the particles at the surface of a liquid that causes a liquid to form round drops
surface tension
a __ is a type of heterogeneous mixture in which the LARGE particles of a material are more or less evenly dispersed throughout a liquid or gas
suspension
gaseous state of a substance that is a solid or liquid at room temp
vapor
groups are __ on the periodic table
vertical columns
which of the following is a compound
water
caused when a single light beam shines through a colloid. the light reflects off of the particles in the substance so that no single beam of light exits the substance
Tyndall Effect
a characteristic that can be observed or detected by using your senses and without changing the sample's composition is
a physical property
this term describes how close the number is to the correct or accepted value of a number. what term is this?
accuracy
done when you are using the knowledge that you have gained to solve a particular problem or answer a specific question
applied research
which of thses isn't a homogeneous mixture
oil and vinegar salad dressing
the __ is a chart that organizes all known elements into a grid of horizontal rows and vertical columns arranged by increasing atomic number
periodic table
a __ is a form of matter that doesn't have a definite volume, no definite shape, and is found in the stars and in lightning
plasma
this term that describes how close a group of measurements are together. they may be nowhere near the correct or accepted value of a number. what term is this?
precision
positive particles that are found inside the nucleus are called the
protons
done when you are just curious about a particular topic
pure research
which of the following is not a heterogeneous mixture
pure water
based upon observations using the senses (color, odor, etc)
qualitative
based upon a measurable amount of something or involves numbers
quantitative
which of the following is NOT a physical change
rotting food
which of the following is a heterogeneous mixture
samples of gaseous argon and solid iron in the same container
smallest particle of an element is called
atom
which of the following is the base unit for time
seconds
which person is responsible for creating the cathode tube which lead to the invention of the tv?
Crookes
which scientist discovered and studied radiation
Curie
this scientist was an english schoolteacher who came up with his own atomic theory
Dalton
which person was credited with being the first person to mention or name atom?
Democritus
the scientist that organized all of the elements into a periodic table is names
Dmitri Mendeleev
which of the following is the base unit for temperature
Kelvin
when one substance changes its identity or becomes a new substance, it goes through a
chemical changes
Fe2O3 is a
compound
seperation technique that produces highly pure solids that look like crystals. this is a good way to make rock candy
crystalization
which of the following is the base unit for length
meters
a __ is a form of matter that doesn't have a definite volume, doesn't have a definite shape, and its particles are spread apart from each other. the particles are whole and not broken apart
gas
substance that's naturally in the gaseous state at room temp
gas
periods are __ on the periodic table
horizontal rows
when two or more substances WON'T mix together easily, it's said that they are this
immiscible
this is controlled by the experiment or scientist
independent variable
this is put on the x-axis when graphing
independent variable
collecting data from a continuous line on the graph that isn't a specific point purposely plotted, but could be between points and connected by the points is called this
interpolation
which of the following is the base unit for mass
kilograms
the __ states that a compound is always composed of the same elements in the same proportions by mass, no matter how large or small the sample. the mass of the compound is equal to the sum of the masses of the elements that make up the compound
law of definite proportions
CO and CO2 are both examples of this law
law of multiple proportions
the __ states that different compounds are formed by the combination of the same elements, different masses of one element combine with the same mass of the other elements in a ratio of small whole numbers
law of multiple proportions
a __ is a form of matter that flows, has definite volume, and takes the shape of its container
liquid
which of the following is the base unit for volume
liters
which of the following isn't evidence that a chemical change has occured
melting
when one substance dissolves or mixes with another substance to form a solution, those substances are said to be
miscible