What is a system?
What you are focused on
What is the transition phase from solid to gas?
Sublimation
This is defined as the ability to do work.
What is energy?
What does Cp represent in q = m x ΔT x Cp
Specific Heat
The ______ the concentration of the hydrochloric acid the more hydrochloric acid particles there are in a given amount of space.
higher
What is the surroundings?
Everything else but the system " so what you are not focused on"
What does the triple point of a substance mean?
Where all three phases for a substance can occur simultaneously/at the same time.
This is the name given to the energy of motion.
What is kinetic energy.
What is the change in temperature of an object whose initial temperature is 40 °C and reaches a final temperature of 65 °C?
15 °C
When a solid lump is cut into pieces, its total surface area ____________.
Increases
Define exothermic reactions. Define endothermic reactions.
Exothermic reaction: release heat energy
Endothermic reaction: absorb heat energy
Which part of the graph represents the gas state?
A
This is the name given to the energy of position.
What is potential energy?
Calculate heat:
m = 20 g, c = 4.18, ΔT = 5°C
must show work
418 J
As the temperature decrease the rate of reaction _______
decrease
Exothermic reactions release heat energy, so is q positive or negative?
negative
What is the transfer of energy an object has due to its motion?
Heat
This is the name for a type of energy that causes atoms to move quicker.
What is thermal energy or heat energy?
A 400 g solid is heated from 15°C to 35°C. The solid has a specific heat of 2.5 J/g·°C. Calculate the heat absorbed, q.
20,000 J
How can the chemical manufacturers make their products quickly and cheaply as possible?
by adding a catalyst.
If water warms up during a reaction, did the reaction absorb or release heat?
Released Heat.
Why do ice cubes left in the freezer for too long become smaller?
Because the ice is going through the process of sublimation, turning directly into water vapor.
What is the total potential and kinetic energy
of particles in an object.
What is thermal energy
A 400 g solid releases 8,000 J of heat as it cools. The solid’s specific heat is 2.0 J/g·°C. Its final temperature is 25°C. Calculate the initial temperature of the solid.
q = m * Cp * (Tfinal-Tinitial)
8000=400*2*(25-Tfinal) --> 8000=800*(25-Tfinal)
8000/800=800/800*(25-Tfinal)
10=25-Tfinal --> 10-25=-Tfinal --> 15°C = Tfinal
For a reaction to happen the collisions must be
Effective (have enough energy, with correct orientation)