Chapter 4 P/C And Energy, Ch 8 Chemical Equations Flashcards
+ symbol meaning?
Plus or added two
placed between substances
Arrow to the right
Yields, produces
Points to products
(s)
Solid state
Written after a substance
(l)
Liquid state
Written after a substance
(g)
Gaseous state
Written after a substance
(aq)
Aqueous solution
Substance dissolved in water
triangle
Heat is added
When written above or below arrow
What’s the difference between physical properties and chemical properties
 Physical properties can be observed/determined WITHOUT CHANGING THE IDENTITY of a substance
Chemical properties FORM NEW SUBSTANCES
Examples of physical properties
SOLUABILITY
phase change properties, like boiling, freezing or melting point
CONDUCTIVITY
Odor, color, shiny
Examples of chemical properties
Flammable,
Decay
Supporting combustion
Ability to rust
No two substances have identical, physical and chemical properties
What’s the difference between a change and a property?
Properties describe
Shiny measurable prop
Changes are verbs with ING
DISSOLVING, CONDUCTING
CUTTING
Are growing a plant and baking physical or chemical changes?
Chemical changes
What are the proper proper terms in writing chemical equations?
Reactants (right YIELDS arrow) products
What is the law of conservation of mass?
Mass can’t be created or destroyed in any chemical or physical process
What is involved in a physical and chemical processes?
Energy
Definition of energy
Ability to do work for capacity to cause change
Name forms of energy
Foods and fuels
Radiant, light, mechanical, electrical, nuclear, heat, chemical, sound
What is kinetic energy
Energy of motion, such as walking down the hall, or rolling a ball
Give an example of potential energy
Foods or a spring
What is the law of conservation of energy?
Energy cannot be created or destroyed. It can only transform from one form to another,
such as plugging in a appliance in a toaster means, changing, electrical, energy to heat, light, mechanical and sound energy.
Official definition of heat
Energy that moves from one place to another due to a difference in temperature
Energy always flows from what to what temperature
High to low temperature
Test
What is specific heat?
Amount of energy needed to change the temperature of 1 g of a specific substance by 1°C
What is temperature?
The measure of kinetic energy of the particles in a sample
What is thermal energy?
Total kinetic energy and potential energy of all the particles in a sample.
This is not warmth but more particles, a swimming pool has more thermal energy than a beaker even if the beaker is boiling and the swimming pool is room temp.
What does a low specific heat mean?
A substance does not need to absorb much energy in order to change its temperature. Metal has a lower specific heat. For example, a metal spoon in a pot is warmer than a wooden spoon in the same pot
Q = energy in joules or calories
C: specific heat
TriangleT =  change in temperature
When energy is released during a chemical reaction, the process is referred to as what
Exothermic
When energy is absorbed during a chemical reaction what is the process called?
Endothermic
In this graph is this endothermic or exothermic? How can you tell?
Endothermic because from reactants to products, the endpoint is higher
In exothermic reactions such as burning, will the product be higher or lower than the reactant on a graph?
The product will be lower
How can energy cause chemical change?
Light causes things to decompose such as hydrogen peroxide
What is an example of forms of energy produced by chemical changes?
Gas in a car, sound, heat
I got this!
Symbols written above the yields arrow in the equation mean what?
It could be a catalyst used to speed up the reaction without being part of the reaction. Or it could be heat or extra info.
What’s the term used for numbers that come before an element in a compound?
Coefficients
Do we ever change the subscript in a correctly written chemical formula?
NO
Is AQ & L the same?
No AQ is dissolved in water/solution,
L equals liquid
Instead of writing gas or precipice, what is sometimes used?
Gas is upward arrow
Precipapte is down arrow
When balancing equations, what do we start and end with?
Start with where you have less
And with oxygen and hydrogen
When balancing equations, how do you reduce?
All or nothing
When looking at a chemical reaction, what do we do first
Formulas first, then balance
During a chemical reaction what is released/absorbed
Energy
Exothermic equals energy released
Endothermic equals energy, absorbed
If there are kilojoules on the
right PRODUCT side
This means what?
It is exothermic
Is photosynthesis endothermic or exothermic?
Endothermic
Where is activation energy on this chart
From the starting line to the top of the hill. This is exothermic as the product is lower than the reaction.
Explain the activity series
It’s a list of elements with the most reactive at the top, and the least at the bottom. It means those above have a greater tendency to lose electrons and they force elements lower on the list to accept electrons.
 Example if copper is placed in solution of silver nitrate, copper has a greater tendency than silver to lose electrons. Silver is forced to accept electrons and will be reduced from +1 toa 0 oxidation state and copper is oxidized/becomes more positive
RS (right arrow) R + S
Is an example of what reaction
Decomposition
starts with one and makes many
Single compound, broken down into two or more simpler products
A + B (right arrow) AB
Is an example of what kind of reaction?
Synthesis
This is ONE thing to the right of the yield arrow
Two or more reactants combine to form ONE product
Also, referred to as COMBINATION reactions
What is the formula for a single replacement?
T + RS (yield arrow) TS + R
Or
U + RS (right arrow) RU + S if halogen kicking out another halogen
The activity series is only used in what kind of reaction
Single replacement
What is the formula for a double replacement?
AB + CD (yield arrow) AD + CB
Cation listed first 
Whatever is written first takes place of the other written first 
Do subscripts travel
NO
In a double replacement if both are aqueous it is what kind of reaction
No reaction
Do we use the activity series for double replacement?
No
Combustion reactions always have the same product which is what
CO 2 and’s H2O
Formula for single replacement?
T + RS= TS + R
The outside ones end up together
When hydrogen gets kicked out, it becomes a what?
Diatomic
Make sure to note 2 atoms!
