Matter Flashcards
Matter
Something that takes up space
Substance
-Any variety of matter that is homogeneous & has a fixed composition by mass
Element
- the simplest form of matter
- CAN’T be broken down by physical or chemical means
ex: C, H, Na
Diatomic elements
2 atoms of the same element bond to form a molecule!!
Compound
- 2 or more different elements chemically bonded
- Can break down into simpler compounds/elements chemically
ex: HCl, KI
Mixture
2 or more substances physically combined
Homogeneous
- Uniform composition
- Solutions
- Aqueous (aq)
Heterogeneous
Contains visibly different substances or phases
How are mixtures different from compounds?
- The components of a mixture can be either elements or compounds
- Mixture separated by PHYSICAL means (compounds by CHEMICAL means)
Monatomic Element
Only one particle just like an element
Mass
-The amount of matter in an object
Volume
-The amount of space an object takes up
What is volume measured with?
mL or cm3.
What is mass measured with?
grams or kilograms
How do you calculate volume?
l x w x h
How do you measure volume with irregular objects?
-Water Displacement
object and water - water = object
Density Formula
D = m/v
Density
Degree of compactness of a substance
What is density measured with?
g/mL or g/cm3
A 5mL sample of ethanol has a mass of 3.95g. What is the density of ethanol?
3.95 / 5
Energy
an object’s ability to do work
Potential Energy
The energy stored in an object
Kinetic Energy
Energy an object possesses due to its motion; directly related to temperature
Temperature vs Heat
Temperature is the average kinetic energy of a sample while heat is the amount of energy flowing from one body of matter to another
How does heat flow?
From hotter to colder objects
How is temperature measured?
Celcius or Kelvin
How is heat measured?
Joules (J)
In Celcius, what are the boiling and freezing pts of water?
0: freezing pt
100: boiling pt
True or False:
When you change by 1C, you also change by 1K
True
In Kelvin, what are the boiling and freezing pts of water?
273: freezing pt
373: boiling pt
How do you change from Celcius to Kelvin?
K = C + 273
Endothermic
- Absorbs energy
- Requires energy as a reactant
Exothermic
- Releases energy
- Produces energy as a product
Is the delta H value for endothermic positive or negative?
+
Is the delta H value for exothermic positive or negative?
-
Chemical Energy
Energy associated with chemical changes and bonds
Atomic/Nuclear Energy
Associated with changes to the nucleus of an atom!
Law of Conservation of Energy
- Energy cannot be created or destroyed
2. Energy CAN be transferred or transformed
What are the 4 ways to separate mixtures?
- Magnet
- Distillation
- Filtration
- Chromatography
How packed are molecules in a solid
Very tightly
How packed are molecules in a liquid
In between tight and loose
How packed are molecules in a gas
Very loose
S ———–> L
Melting (Fusion)
L ———–> S
Freezing
S ———-> G
Sublimation
G ———-> S
Deposition
L ———-> G
Vaporization
G ———-> L
Condensation
On a phase change graph, on the inclines what are on them?
Solid, Liquid, Gas
On the phase change graph, on the straight parts are?
Phase changes:
- Freezing/Melting
- Boiling/Condensation
Can kinetic and potential energy increase or decrease at the same time?
No! That’s why when kinetic increases, the potential remains the same, and when potential increases (straight part of the graph) kinetic remains the same
What is a cooling curve?
A phase change graph decreasing (backward)
What happens to potential and kinetic energy in a cooling curve decrease?
- Potential energy remains unchanged
- Kinetic energy decreases
What happens to kinetic and potential energy in a cooling curve straight-line part of graph?
- Kinetic energy remains unchanged
- Potential energy decreases
Calorimetry
Measuring and Calculating Heat
Calorimetry equation
q = mC∆T
What do q, m, c, and ∆T mean?
q = heat m = mass c = specific heat (Table B) 4.18 ∆T = temperature change
Specific Heat:
The amount of heat per gram
required to raise the
temperature by one degree
Celsius
When do you use the heat of fusion equation?
When the phase change is melting/ freezing
When do you use the heat of vaporization equation?
When the phase change is boiling or condansation
Heat of Vaporization equation
q = mHv
q = heat m = mass Hv = 2260
Heat of Fusion equation
q = mHf
q = heat m = mass Hf = 334
Energy is absorbed when:
liquid to gas or
solid to liquid
Energy is released when:
gas to liquid or
liquid to solid
The arrangement of particles is most ordered when the phase is…
SOLID
Physical Change
something that changes the physical properties of a substance
-size, shape, form
Chemical Change
a reaction that rearranges the particles of two or more substances to create at least one new substance
Which change forms a NEW substance?
A chemical change
Which change changes the shape, size, or form?
A physical change
Which change can be undone?
A physical change
Which change may release heat, odor, sound, or light
A chemical change
What is the acronym for noble gases?
Br I N Cl H O F
In distillation, which boiling pt boils off first?
The lower one
