Intro to Energy. Flashcards
What is chemistry all about?
Matter.
What is the universe?
Matter and energy.
What do changes in a system involve?
A movement of matter driven by a flow of energy.
When something is happening, energy is what?
Flowing.
What is energy?
Energy is the capacity to do work or produce heat.
What are the two types of energy?
Potential and kinetic energy.
What is kinetic energy?
The energy of motion.
What is potential energy?
Energy that is stored.
What are some different types of potential energy.
Chemical, nuclear, gravitational, and elastic energy.
What is chemical energy?
Energy stored in chemical bonds.
What is nuclear energy?
Energy stored in the nuclei of atoms.
What is gravitational energy?
Energy that is based on gravity.
What is elastic energy?
Energy of compressible or stretchable objects.
What are different types of kinetic energy?
Thermal, electrical, electromagnetic energy.
What is thermal energy?
The total energy of all vibration particles that make up an object.
What is electrical energy?
Kinetic energy of charged particles.
What is electromagnetic radiation?
Microwaves, x-rays, and visible light.
What SI unit do we use for energy?
The joule.
One calorie of heat does what to water?
It raises the temperature of 1g of pure water.
What is a Calorie (capital c)?
The energy content of foods and beverages.
How many calories is one Calorie?
1 Calorie = 1000 calories.
How many joules is equal to one calorie?
4.184 joules.
What is thermochemistry?
The study of energy changes that happen during chemical reactions or changes of state.
How can changes in energy be detected?
By observing heat transfers.
What is heat?
Heat is the energy that transfers from one object to another because of a temperature difference.
How does heat flow from object to object?
Heat flows from a warmer object to a cooler one.
What is power equal to?
the rate of energy flow (watts).
What is the law of conservation of energy?
Energy is not created or destroyed, only transferred or transformed.
What is temperature?
The measure of the average kinetic energy of the particles in a material.
More heat is equal to?
Higher temperature, but the change will vary depending on the substance
What is specific heat (c)?
The amount of energy needed to increase the temperature of a substance by 1 C.
How will materials that have high specific heats heat up?
They will heat up more slowly since it takes more energy to see the temp difference.
How will material that have low specific heats heat up?
They will heat up quickly since it takes less energy to see temp difference.
What is heat measured in?
Joules or calories.
What are the three types of energy transfers?
Conduction, convection, radiation.
What is conduction?
Heat that is transferred through touch.
What is convection?
The rising/falling of substances due to heating/density difference.
What is radiation?
Waves/energy.
When does thermal conduction occur?
It occurs through oscillation of adjacent atoms.
What is thermal conduction?
Energy passed through collisions of atoms.
What is thermal conductivity?
How efficiently energy is conducted.
What is conduction better in when it comes to states of matter?
Solids.
What are low conductivities?
Insulators.
What are great conductors?
Metals, due to the availability of valence electrons.
Convection is the cycling of what?
Fluids given by differences in density.
At high temperature molecules do what?
Molecules spread, they are less dense, and they rise.
At low temps molecules do what?
Molecules spread out less, they are more dense, and they sink.
What is viscosity?
A measure of a fluids resistance to flow.
Atoms do what with radiation?
They absorb radiation and reemit it.
Frequency and total amount of energy of the emitted radiation are functions of what?
The temperature of an object.
