2. for the following questions, use a periodic table and your atomic calculations to find the unknown information about each isotope: you have a helium isotope with 2 neutrons. how many electrons are there? 0 2 4 6

Determine the net charge of the predominant form of arg at (a) ph 1.0, (b) ph 5.0, (c) ph 10.5, and (d) ph 13.5

Which type of reaction is shown in this energy diagram? energy products activation energy reactants time o a. endothermic, because energy is released to the surroundings o b. exothermic, because energy is absorbed from the surroundings o c. exothermic, because energy is released to the surroundings o d. endothermic, because energy is absorbed from the surroundings

Amerry-go-round of radius r, shown in the figure, is rotating at constant angular speed. the friction in its bearings is so small that it can be ignored. a sandbag of mass m is dropped onto the merry-go-round, at a position designated by r. the sandbag does not slip or roll upon contact with the merry-go-round. how would you rank the following different combinations of m and r on the basis of the angular speed of the merry-go-round after the sandbag "sticks" to the merry-go-round from largest to smallest. a) m = 10kg, r = 0.25r b) m = 20kg, r = 0.25r c) m = 10kg, r = 0.50r d) m = 10kg, r = 1.0r e) m = 15kg, r = 0.75r f) m = 40kg, r = 0.25r