Thermodynamics Quiz

review notes, lab, worksheets

kinetic molecular theory

matter is made up of tiny particles that are always in motion; particles move faster as the temperature increases and transfer energy during collisions

states of matter

solid, liquid, gas

kinetic molecular theory

matter is made up of tiny particles that are always in motion; particles move faster as the temperature increases and transfer energy during collisions

states of matter

solid, liquid, gas

phase diagram

shows the phase of a molecule according to the pressure and temperature of the environment

triple point

point where all 3 states of matter exist in equilibrium

critical point

point where the substance can no longer be distinguished between a liquid and a gas; exists as a supercritical fluid

melting

change from solid to liquid

freezing

change from liquid to solid

vaporization

change from liquid to gas

condensation

change from gas to liquid

sublimation

change from solid to gas

deposition

change from gas to solid

endothermic

reaction or change that absorbs heat

which phase changes are endothermic

melting, boiling, sublimation

exothermic

reaction or change that releases heat

what phase changes are exothermic

freezing, condensing, deposition

what formula is used for A, C, and E

q = mcΔT

what formula is used for B and D

q = mΔH°

when to use q = mcΔT, q = mΔH°

use q = mcΔT as temperature increases, use q = mΔH° when a phase change occurs

why doesn’t the temperature change during a phase change?

the added heat is being absorbed to break the IMFs between molecules rather than increasing kinetic energy

what does q represent

heat in J or kJ

what does m represent

mass in grams or moles

what does c represent

the specific heat of a substance

what does ΔT represent

change in temp (final temp - starting temp)

specific heat

heat required to raise the temperature of the unit mass of a given substance by one degree

heat of fusion (ΔH_f)

amount of energy required for a substance to melt

heat of vaporization (ΔH_v)

amount of energy required for a substance to vaporize

calorimetry

process of measuring the amount of heat released/absorbed during a chemical reaction

calorimeter

device used to measure the absorption or release of heat

why is styrofoam used as a calorimeter?

it is an excellent insulator, meaning that minimal heat will escape the system

if in calorimetry, the metal released 100J of energy, how much energy did the water absorb?

100J (heat loss = heat gained)