How many grams of NaBr are present in 1.2 L of 0.15 M NaBr solution?

Frictional forces acting on an object are often converted into energy, which causes the temperature of the object to rise slightly.

In the millikan oil drop experiment they determined that every drop had a charge which was a while number multiple of -1.60x10^-19. if a drop has a total charge of -9.60x10^-19 then how many excess electrons are contained within the drop?

Which of the following are correct values for the ideal gas laws constant r