Are these a compound, element, mixture of compounds, mixture of elements, and compounds or mixture of elements.

Arollercoaster car at the top of a hill has potential energy kinetic energy chemical energy light energy

If a solution is considered basic, then a) the hydroxide ion and hydronium ion concentrations are equal. b) the hydroxide ion concentration is less than the hydronium ion concentration. c) the hydronium ion concentration is greater than the hydroxide ion concentration. d) the hydroxide ion concentration is greater than the hydronium ion concentration.

Asample of aluminum foil contains 8.60 × 1023 atoms. what is the mass of the foil?