Who discovered a pattern to the elements in 1869?

A dehydration reaction starting with 3.8 g cyclohexanol produces 2.6 g cyclohexene. Calculate the theoretical yield for this reaction. Report your answer with two significant figures.

Why phosphorus forms 3 bonds in molecule such as PH3 and PCl3-

And Endothermic reaction is ...

Which of the following would increase the solubility of a gas in water? 1. increase the temperature of the water 2. decrease the temperature of the water 3. increase the pressure of the gas above the water

Use the partition function for a harmonic oscillator, q = 1 / (1 - e^-hv/kBT), to determine the ratio of populations in the lowest and first excited energy levels, P0/P1, for the indicated systems at two temperatures, 50 K and 298 K: (a) The 1700

The type of nuclear decay an unstable nucleus will undergo depends on its ratio of neutrons to protons. The radioisotope cobalt-65 has a ratio of neutrons to protons of 1.41, which is too high for a nucleus of this size.

1.87 $/gal to dollars per liter, Express your answer using three significant figures.

What can a student do to increase the force of attraction of a magnet on an iron block?

Which elements can react to produce a molecular compound?

Who created the periodic table and in what year?