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Definitions
Hess's Law
q=mc∆t
Exothermic and Endothermic reactions
Nuclear
100
The amount of energy transferred between substances.
What is enthalpy change?
100
Hess discovered 2 rules for chemical equations and enthalpy changes
What is if a chemical equation is reversed, them the sign of ∆H changes or if the coefficients of a chemical equation are altered by multiplying or dividing by a constant factor, then the ∆H is altered in the same way?
100
Rearrange the equation q=mc∆t to solve for mass
What is m=q/c∆t?
100
If the products have a higher potential energy the reaction is.
What is an endothermic reaction?
100
What reaction has the most energy chemical, physical, nuclear and why?
Nuclear because it involves splitting of an atom.
200
A set of reactants and products under study usually represented by a chemical equation.
What is a chemical system?
200
Explain what the reason of the use Hess's law is.
Answers may vary, but the reason for the use of Hess's law its to use known enthalpies of reactions to get to the target reaction's enthalpy.
200
How do you find molar enthalpy of q
Find the ∆H of q which is ∆H=±q then find the moles of ∆H which is ∆H=∆H/n
200
On a graph the reactants are higher than the products.
What is a exothermic reaction?
200
The way that nuclear power plants get there energy
What is nuclear reactions that heat up water and cause steam to flow and this steam powers a turbine?
300
An ideal system in which neither matter nor energy can move in or out.
What is an isolated system?
300
Create a equation to measure the target enthalpy in a set of equations.
What is ∆H=∑∆H or ∆H= ∆H1 + ∆H2 + ∆H3...?
300
What mass of lithium chloride must have dissolved if the temperature of 200g of water increased by 6.0°C? The molar enthalpy of solution of lithium chloride is -37KJ/mol
The mass is 5.7g
300
C10H8 + 12 O2 → 10 CO2 + 4 H2O ∆H=+ 21334KJ this reaction is
What is an endothermic reaction?
300
The benefits of nuclear power.
What is less pollution, reduces dependence of fossil fuels for electricity generation, has low uranium fuel costs?
400
A change in the form of a substance in which no chemical bonds are broken.
What is a physical change?
400
Using the Hess's law equation claculate ∆H of the target reaction when you have 3 other reactions 1. -356KJ 2. +334KJ 3. +3450000J
What is 3,428KJ because the third number is in joules not kilojoules?
400
The reaction of methane and a flame
What is an exothermic reaction
400
The disadvantages of nuclear power (name 2)
What is the possible release of radioactive materials, the difficulty of disposing highly toxic radioactive wastes, the large cost to build the power plants , unknown health effects, thermal pollution from cooling water.
500
A graphical representation of the energy transferred during a physical or chemical change
What is a potential energy diagram?
500
6C + 8H2 + O2 + 2C3H7OH This is your target reaction with this find what ∆H total will be if known equations are 1) C3H7OH + 9/2 O2 ---> 3CO2 + 4H2O ∆H= -2008 KJ 2)C + O2 ---> CO2 ∆H= -349 KJ 3)H2 + 1/2 O2 ---> H2O ∆H= -286 KJ
∆H total is -636KJ this is because you multiply the first equation by (-2), the second equation by (6) and the third equation by (8) then find the sum of all equations.
500
If 3.20g of propane burns, what temperature change will be observed if all of the heat from the combustion transfers into 4.0 kg of water C3H8 + 5O2--->3CO2 + 4H2O
What is ∆T=9.6°C
500
Is photosynthesis a endothermic reaction or exothermic reaction and why
It is an endothermic reaction because sun energy is being put into the chemical reaction?
500
The amount of power generated in Canada that strictly nuclear is a) 20% b)74% c)66% d) 15%
What is d)15%