8 th Science 12/2013 Flashcards
density
the amount of mass per unit of volume
The desity of an object is determined by
how tightly packed together the matter is
the unity for density is
g/ml or g/cm3
anything that takes up space is made of
matter
physical properties of a substance
characteristics of the substance such as, color, smell, taste, hardness, state of matter, temperature changes, density, mass, volume, malleability, solubility
chemical properties
determined by a substance’s ability to react with other substances such as, water/ acids.
Examples of chemical property - the color of a sunset, the shape of a leaf, the ability of gunpowder to explode.
The ability of wood to burn is a ______________ property
chemical
The hardness of a diamond is ________________________ property.
physical
In a chemical change, what happens to the original substances?
They combine/react to form a new substance
examples of what happens in a chemical change:
impossible to reverse.
Oxidation creates rust. That’s an example of a _________________ reaction.
chemical
When you digest food, that is an example of _______________________ change.
chemical
When Ice melts and becomes water, that’s a ____________________ change.
physical
Vinegar is mixed with baking soda and releases carbon dioxide gas. That’s a ___________________ reation.
chemical
a pencil is sharpened and leaves behind shavings. That’s a __________________ change.
physical
Color, shape and texture are ____________________ properties.
physical
mass is the amount of _____________________.
matter is the amount of space an object takes up.
a person’s weight changes when on the moon, but her ____________________ stays the same.
mass
What do you call the method of measuring the mass of irregularly shaped solids? (Think about putting it in water)
What unit is used to measure it?
displacement
mL ( milliliters)
endothermic change
a chemical reaction that requires heat
exothermic change
chemical reaction in which heat is produced and released into the environment
What do we use a spring scale to measure?
weight
What do we use to measure mass?
a balance
To find an object’s density, first measure its _______________ and _________________. Then use the equation: ____________________
first measure its mass, then volume, then use the formula D=m/V
what are the three four states of matter?
solid, liquid, and gas and plasma
Is flammability a physical or chemical property?
chemical
The properties that are the most useful in identifying a substance are ________________________ properties.
Characteristic properties are most useful in identifying a substance. (Both physical and chemical)
Particles of which state of matter (solid, liquid, or gas) move the fastest and are the farthest apart.
gas
Which state of matter has a definite shape and volume.
solids
Viscosity describes a liquid’s resistance to _____________________.
Viscosity is the term that refers to a liquid’s resistance to flow. (ex: honey flows much slower than water; it has a higher viscosity)
Length x height x width = _________________
volume
a form of matter that does not have a definite volume or shape is ____________
gas
Erosion of soil is an example of a _________________ change.
physical
The ability of an element to be molded or flattened is called
malleability
How does a liquid become a solid?
when the temperature is lowered to a liquid’s freezing point, it becomes solid
What is the SI unit for length?
(m) meter
What is the SI unit for volume?
(L) liters
(mL) milliliters
What is the SI unit for mass?
(kg) kilograms
(g) grams
(mg) milligrams
What is the SI unit for temperature?
(K) Kelvin
(C) Celsius
What tool do scientists use to measure temperature?
thermometer
Condensation is the change of state from a ___________________ to a ____________.
from a gas to a liquid
The ________________________ is the point at which a liquid boils.
boiling point
_______________ is the change from a liquid state to a gas state,
evaporation
____________________ is the process in which a solid directly changes into a gas.
sublimation
What is the melting point of ice?
What is the freezing point of water?
0 degrees Celsius
If energy is added, it melts
if energy is removed, it freezes
Plasma is different from gas because ____________________________.
The atoms are different. Plasma is made up of positively and negatively charged particles and the electrons are free to move around, rather than bound to the nucleus, as in gasses.
Ex: neon lights, the Northern Lights
The temperature of a substance is related to the speed of that substance’s __________________________.
particles
__________________ is added during endothermic changes.
Energy
What is different about the movement of particles in a solid vs. a liquid?
The particles move more in a liquid and spread out. In a solid, the particles barely move - just vibrate.
chemical properties describe a substance based on its ability to _____________ into a _________________________ substance that has different __________________________.
based on its ability to change into a new substance that has different properties
