Define calorimetry
what is the science of measuring the amount of heat energy released or absorbed during a chemical reaction or physical change.
Define enthalpy
What is a measure of the total energy of a system, including its internal energy and the energy associated with pressure and volume. It’s often used in thermodynamics to understand heat changes during reactions at constant pressure.
This classic Halloween fruit is often carved into spooky lanterns and is also a popular pie filling. What is it?
What is a pumpkin?
If you have 2.50 moles of NaCl, what is the mass of NaCl in grams? (Molar mass of NaCl = 58.44 g/mol)
What is 147.1 g?
You are brewing a potion that requires 100 g of water at 25.0°C. If you want to raise the temperature to 80.0°C, how much heat is needed? (Specific heat capacity of water = 4.18 J/g°C)
What is 22,900 J (or 22.9 kJ)?
In a calorimetry experiment, if 50.0 g of water absorbs 2100 J of heat, what is the change in temperature if the specific heat capacity of water is 4.18 J/g°C?
What is 10.05 °C.
Which sign for heat transfer (q) indicates that a system is absorbing heat from its surroundings? (a) + (b) -
What is (a) +?
In which country did the tradition of Halloween originate?
What is Ireland?
How many moles are present in 25.0 grams of glucose (C₆H₁₂O₆)? (Molar mass of glucose = 180.18 g/mol)
What is 0.139 moles?
In your cauldron, you mix 50.0 g of a hot metal at 150.0°C with 150.0 g of water at 25.0°C. If the final temperature of the mixture is 30.0°C, how much heat did the metal lose? (Specific heat capacity of water = 4.18 J/g°C)
What is approximately 2,500 J?
When 0.250 moles of a substance releases 1500 J of heat during a reaction, what is the ΔH°rxn in kJ/mol?
What is -6.00 kJ/mol?
In a process where a system does work on the surroundings and loses heat, what would be the signs for q and w? (a) q=+,w=— (b) q=−,w=—
What is (b) q=−,w=−?
In folklore, a vampire is said to be repelled by this common herb, often used in cooking. What is it?
What is garlic?
If 4.00 moles of a gas occupy a volume of 88.8 liters at standard temperature and pressure (STP), what is the molar volume of the gas?
What is 22.2 L/mol?
To create a glowing potion, you mix 200 g of a solution with an enthalpy change (ΔH) of +150 kJ/mol. If the solution reacts to produce 0.25 moles, what is the total energy change for your potion?
What is +37.5 kJ?
In a calorimetry experiment, 100.0 g of a metal initially at 150.0°C is placed in 200.0 g of water at 25.0°C. If the final temperature of the system is 30.0°C, how would you determine the specific heat capacity of the metal?
0.348 J/g°C.
Calculate the change in internal energy (ΔU) for a system that gives off 45.0 kJ of heat and performs 855 J of work on the surroundings.
(a) 44.1 kJ
(b) -44.1 kJ
(c) -45.9 kJ
(d) 9.00 × 10² kJ
What is (c) -45.9 kJ?
This famous author, known for his horror stories, wrote "The Tell-Tale Heart" and "The Raven." Who is he?
Who is Edgar Allan Poe?
Calculate the number of molecules in 3.00 moles of water (H₂O). (Use Avogadro's number:
6.022×10^23 molecules/mol)
What is 1.81×1024 molecules?
You have a potion that releases 75.0 kJ of heat when 0.50 moles of a reactant is consumed. What is the ΔH°rxn for the reaction per mole of reactant?
What is -150 kJ/mol?
A reaction in a bomb calorimeter produces 3000 J of heat and involves the combustion of 0.5 moles of a hydrocarbon. Calculate the ΔH°combustion in kJ/mol for this hydrocarbon.
What is -6.00 kJ/mol?
How much energy is required to decompose 765 g of PCl₃, given that its molar mass is 137.32 g/mol and the reaction has a ΔH°rxn of +1207 kJ? (a) 2.31 × 10³ kJ
(b) 4.33 × 10³ kJ
(c) 6.72 × 10³ kJ
(d) 1.68 × 10³ kJ
What is (a) 2.31 × 10³ kJ?
What is the fear of Halloween called?
What is Samhainophobia?
How many grams of CaCO₃ are needed to obtain 0.500 moles? (Molar mass of CaCO₃ = 100.09 g/mol)
What is 50.0 g?
While brewing your potion, you add 250 g of a substance that absorbs 500 J of heat. If the initial temperature of the substance is 20.0°C and the specific heat capacity is 2.0 J/g°C, what is the final temperature of the substance?
What is 20.5°C?