Identify the following mineral: hardness that a copper penny will scratch; color black; pearly luster.
talc
mica
gypsum
horneblende

How air particles exert a pressure on the inside of the balloon

What determines the average kinetic energy of the particles in a gas? a. the number of collisions b. the number of particles c. the size of the particles d. the temperature

The human eye contains a molecule called 11-cis-retinal that changes shape when struck with light of sufficient energy. the change in shape triggers a series of events that results in an electrical signal being sent to the brain that results in vision. the minimum energy required to change the conformation of 11-cis-retinal within the eye is about 164 kj/mol.