a scientist obtains a small block of sodium. Sodium is a soft silvery metal. She places the block of sodium in a beaker filled with 50mL of water. What are the reactants in this chemical reaction? and explain the evidence int the products for the chemical reaction?

Arailroad car collides with and sticks to an identical railroad car that is initially at rest. after the collision, the total kinetic energy of the two cars is a) the same as before. b) half as much as before. c) one third as much as before. d) one fourth as much as before. e) twice as much as before.