Write a balanced chemical equation for the decomposition of solid sodium sulfide in aqueous solution. a) na2s(s) → na+(aq) + s(s) b) nas2(s) → na+(aq) + 2s2-(aq) c) na2s(aq) → 2na+(s) + s2-(s) d) na2s(s) → 2na+(aq) + s2-(aq)

You are given a vector a = 125i and an unknown vector b that is perpendicular to a. the cross-product of these two vectors is a × b = 98k. what is the y-component of vector b?

The mass of a bowling ball is 10 kg and the mass of a ping pong ball is 0.015 kg. if the two objects are 5 meters apart, what is the gravitational force ?

Two 2.0-cm-diameter disks face each other, 1.0 mm apart. they are charged to ±10 nc. what is the electric field strength between the disks? a proton is shot from the negative disk toward the positive disk. what launch speed must the proton have to just barely reach the positive disk?