What is the empirical formula of a compound that is 13.76% lithium, 30.71% phosphorus , and 55.53 % oxygen .

Which statement describes the phase change that occurs when dry ice is placed in an open container at room temperature?

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.

Use the periodic table to identify the number of core electrons and the number of valence electrons in each case below. potassium (k): 1s22s22p63s23p64s1