Two balls of lead have different size. do they have the same density?

The molality of calcium chloride (cacl2) in an aqueous solution is 2.46 m. what is mole fraction of the solute?

When the chemicals iron sulfide (fes) and hydrochloric acid (hcl) are combined, bubbles appear from the mixture. 1. does the appearance of bubbles indicate a physical or chemical change? 2. why do the bubbles indicate this change? 3. what property is this?

Avolleyball player hit a ball with a mass of 0.25 kg. the average acceleration of the ball is 15.5 m/s². how much force did the volleyball player apply to the ball? 62.0 n 3.87 n 62.0 m/s² 3.87 m/s²