Need answers asap! my science grade is at 84 and if i don't get it higher i'll be grounded in two weeks 11) a plastic ball floats on the water. what do you know about its density? a. the plastic ball has a density greater than water. b. the plastic ball has a density less than water. c. the water has a density less than the plastic ball. d. the plastic ball and the water have the same density. e. nothing can be determined about the density of the ball. 12) how do you know a chemical change has occurred? a. new bonds have formed or bonds have broken. b. the matter has had a change in state. c. the temperature has changed. d. all of the above e. only a and c are indicators of a chemical change. 13) if a chemical bond is formed or destroyed, what changes? a. energy is absorbed or released. b. protons are absorbed. c. neutrons will vary. d. energy is destroyed. e. protons are released.

For you first question. Your answer is B, its a lighter density. If something floats on top of the water, its density is lighter then the water. If it sinks, that means its density is heavier.

definition

                    entropy is a measure of the randomness or the extent of disorder of a chemical process.

                      enthalpy is a measure of the heat change of a reaction occurring at a constant pressure.

measurement units:

                        entropy is measured in joule per kelvin (jk⁻¹)   whereas enthalpy is measured in joule per mole (jmol⁻¹)

requirements:

                            entropy has no requirements or limits, and its change is measured by the division between the heat change of the chemical process and the temperature.

                              in contrast, enthalpy can only be related to the heat change of the reaction under standard conditions.