Which set of procedures and observations indicates a chemical change?
(1) ethanol is added to an empty beaker and the ethanol eventually disappears.
(2) a solid is gently heated in a crucible and the solid slowly turns to liquid.
(3) large crystals are crushed with a mortar and pestle and become powder.
(4) a cool, shiny metal is added to water in a beaker and rapid bubbling occurs.

Stage in which a typical star has completely stopped fusion

How hot is the suns corona? (integrated science)

According to the valence shell electron pair repulsion (vsepr) theory, a molecule that has four electron groups around the central atom will exhibit what electron geometry? view available hint(s) according to the valence shell electron pair repulsion (vsepr) theory, a molecule that has four electron groups around the central atom will exhibit what electron geometry? trigonal bipyramidal tetrahedral square planar determination of electron geometry requires information on whether the electron groups are lone pairs or bonding groups.