C3.3 Calculating And Explaining Energy Change Flashcards
How can you change calorimetry to be better?
Put heat proof mats up
Copper cup
What’s calorimetry?
Testing fuels for heat exchanges
How do you find the energy?
Q=MC^T
What does Q=MC^T stand for?
Energy= mass of water x specific heat capacity (4.18) x temperature change
How do you find energy per mole?
Divide by mass
Times by Mr
In the reaction A+B=C+D if it’s exothermic which has a greater enthalpy?
Products
In the reaction A+B=C+D if it’s endothermic which has a greater enthalpy?
Reactants
Is a exothermic reaction a positive or negative enthalpy change?
Negative
Is a endothermic reaction a positive or negative enthalpy change?
Positive
What happens in a exoteric reaction?
Heat lost so temperature increase
In a energy change diagram which are higher products or reactants in an exothermic reaction?
Reactants
In a energy change diagram which are higher products or reactants in an endothermic reaction?
Products
Name 2 examples of exoteric reactions?
Combustion
Respiration
Give 2 examples of an endothermic reaction?
Thermal decomposition
Photosynthesis
How do you work out energy released from a reaction?
Bonds broken-bonds formed
What do catalysts do?
Reduce Ea
How does a hydrogen fuel cell work?
Turns the hydrogen and oxygen to ions then puts an electric current through do they react and water and energy comes out
Advantages of hydrogen fuel cells?
Renewable Cheap Sustainable Efficient No waste products
Disadvantages of hydrogen fuel cells?
Cars are more expensive Have to get a new car Hard to store gas Explosive No infrastructure
