Which of the following is an example of a model?

a) pv=nrt

b) a geographical map

c) a belief that aliens exist

d) all of the above

Does the energy in a solid increase or decrease when changing to a liquid?

Acalorimeter is to be calibrated: 51.203 g of water at 55.2 degree c is added to a calorimeter containing 49.783 g of water at 23.5c. after stirring and waiting for the system to equilibrate, the final temperature reached is 37.6 degree c. specific heat capacity of water (s = 4.18 j/g∙degree c). calculate the calorimeter constant. (smδt)warm water = -[(smδt)cold water + (calorimeterδtcold water)]

State one important difference between a physical change and a chemical change?