Evidence of a chemical change includes?

Which symbol can be used to indicate the pressure at which a chemical reaction is carried out? 25°c 2 atm pa

Which of these is an example of pseudoscience? a) predicting the time of sunrise based on data on position of earth b) predicting the date of the moon phases based on data on position of earth c) predicting eclipses based on the position of the sun and the moon d) predicting future events in a person's life based on the position of the moon

An alpha particle is: a hydrogen atom a nucleus of helium two neutrons an electron