What explains the fact that no machine is 100 percent efficient?

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To calculate percent by mass, use the equation below: calculate the percent by mass of each element. %n = % %h = % %o = %

Some molecular compounds, such as hcl, ionize completely in solution. for molecular compounds such as h2co3, most molecules do not ionize in solution. which describes the properties of these two solutes? a. hcl and h2co3 have the same effect on the properties of the solution. b. hcl raises the freezing point of water more than h2co3 does. c. hcl raises the boiling point of water more than h2co3 does.