A ball of mass 0.450 kg and a velocity of + 8.00 m/s collides head-on with a ball of mass 1.00 kg that is initially at rest. No external forces act on the balls. After the collision, the velocity of the ball which was originally at rest is + 3.38 m/s. What is the velocity of the 0.450 kg ball?

Which of the following statements is true? a. elements in the last period are radioactive. b. atomic weight is the same as atomic mass. c. elements in the same group have the same number of electron shells. d. atomic number equals the number of neutrons in the nucleus of an atom.

Which of the following is always a reactant in a combustion reaction? oxygen nitrogen hydrogen carbon

The following reaction shows sodium carbonate reacting with calcium hydroxide. na2co3 + ca(oh)2 → naoh + caco3 how many grams of naoh are produced from 20.0 grams of na2co3? (molar mass of na = 22.989 g/mol, c = 12.01 g/mol, o = 15.999 g/mol, ca = 40.078 g/mol, h = 1.008 g/mol) 12.2 grams 15.1 grams 24.4 grams 30.2 grams