Atoms of elements in the same group have the same number of [blank] this is why they have similar chemical properties.
a. protons
b. neutrons
c. valence electrons

Water at room temperature of 20.0°c is poured into an aluminum cylinder which has graduation markings etched on the inside. the reading in the graduations is 300.0 cc. the cylinder with the water in it is then immersed in a constant temperature bath at a temperature of 100°c. what is the reading for the level of water on the graduations of the cylinder after the water and the cylinder reach thermal equilibrium with the bath? the volume coefficient of expansion of water is 2.07 x 10^-4 k-1, and the linear coefficient of expansion of aluminum is 23.0 x 10^-6 k-1. a) 305.0 cc b) 304.0 cc c) 303.5 cc d) 303.3 cc e) 304.5 cc

How is the gravitational force related to the distance between two objects?

Aball is thrown horizontally from a cliff at 8m/s .in what direction is the ball moving 2s later?