Which of the following would best describe the characteristics of covalent materials? select one:
a. a. a brittle, transparent solid with a very high melting point.
b. b. a shiny, malleable solid with a very high melting point.
c. c. a non-conducting material with low melting and boiling points, likely liquid or gas at room temperature.
d. d. a brittle, opaque solid with a very high melting point.
e. e. a non-conducting solid at room temperature that will conduct if melted or dissolved.

Which statement is true according to the kinetic theory? a. molecules of different gases with the same mass and temperature always have the same average density. b. molecules of different gases with the same mass and temperature always have the same average volume. c. molecules of different gases with the same mass and temperature always have the same pressure. d. molecules of different gases with the same mass and temperature always have the same molecular mass. e. molecules of different gases with the same mass and temperature always have the same average kinetic energy.