Why would an unstable radioactive isotope (nuclide) emit a beta particle (high energy electron)? A)It has too many neutrons
B)It has too many protons
C)It has too many electrons
D)It has too few electrons

Agroup of students is studying convection currents. they fill two identical balloons with the same amount of helium. one balloon is placed in a freezer and the other in an area with warm air. after 10 minutes, the balloons are released from a height of 1 meter. which of the following do the students most likely observe? a. the balloons both rise. the cold balloon is larger than the warm balloon. b. the balloons rise at the same rate. both balloons are the same size. c. the warm balloon expands and rises. the cold balloon shrinks and sinks. d. the cold balloon expands and rises. the warm balloon shrinks and sinks.

Achemical equilibrium between gaseous reactants and products is shown. n2(g) + 3h2(g) ⇌ 2nh3(g) how will the reaction be affected if the pressure on the system is increased? it will shift toward the reactant side as there is lower pressure on the reactant side. it will shift toward the product side as there is higher pressure on the product side. it will shift toward the reactant side as there are a greater number of moles of gas on the reactant side. it will shift toward the product side as there are a fewer number of moles of gas on the product side.

1) a light bulb takes in 30 of energy per second. it transfers 3j as use energy. calculate the efficiency. second. it transfers 3j as useful light energy and 27j as heat energy. calculate the efficiency