Stars normally convert hydrogen into helium through nuclear fusion. This requires incredibly hot temperatures and high pressure. At the moment, the temperature of empty space is nowhere near warm enough to fuse any elements together. What type of temperature and pressure conditions needed to be present in the early universe in order to create the first hydrogen atoms?

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.

asthenosphere and convection

wire in brush may conduct electricity from cell to drill and vice versa electrc shock possible