In the first law of thermodynamics, ΔE=Q−W , what does ΔE stand for? the change in the internal energy of the system

the work done by the piston

the heat added to the system

the internal energy of the system

freezing

deposition

condensation

explanation;

melting also called fusion is the process where solid becomes liquid, sublimation is the process where solid becomes gaseous without first changing to liquid, deposition involves change from gaseous to solid state, freezing involves change from liquid to solid, boiling or evaporation involves change of liquid to gaseous state, while condensation is the change from gaseous state to liquid state.

endothermic reactions involves absorption of heat from the surroundings or the environment while exothermic reactions involves loss of heat energy to the surroundings.

in this case, sublimation, evaporation and melting are endothermic reactions (gain energy from the environment) while, freezing, deposition and condensation are exothermic (loss of energy to the surroundings) reactions.

the five characteristics of adolescence are biological growth and development, and undefined status, increased decision making, increased pressure and the search of self.

it is a negative acceleration

float.

archimedes' principle

denser than water sinks in water.

denser than mercury would sink in it