When did Pangaea begin to break apart?

a. 20 million years ago

c. 250 million years ago

b. 100 million years ago

d. 2 billion years ago.

What is the value of k, at 25 degrees Celsius

Fusion reactions occur between what kinds of elements?

Cation a has a + 3 charge and is small. cation b has a + 1 charge and is large. which is more likely to occupy negatively charged sites on a clay mineral given equal concentrations in solution? cation a cation b they are the same

Look up the first ionization energies of silver and manganese; which of these two elements would you call more metallic based on the way we define it in this book?

A beam of radiation has an energy of 2.39*10^2 kJ/mol. What is the wavelength of this light?

Which of the following characteristics is fixed, or definite, for all states of matter? volume shape mass energy

Describe a change caused by kinetic energy as well as a change caused by potential energy.

Which is more concentrated, a solution (1) prepared by dissolving 21.0 g of naf (0.500 mol) in enough water to make 500 ml of solution or a solution (2) prepared by dissolving 10.5 g (0.250 mol) of naf in enough water to make 100 ml of solution?

Hi i need hel does any one know what P3N2 means?.-.

How does thermal energy transfer when a room is heated by a furnace?