Select all the correct answers. A sample of an unknown compound has a percent composition of 52.14% carbon, 13.13% hydrogen, and 34.73% oxygen. Which compounds could the sample be? CH3CH3CH2O2 C2H5OH C4H10O2 C4H12O2 CH3CH3CH2OOH

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

The boiling point of propanoic acid is higher than that of 1-butanol because: propanoic acid has a higher molecular weight than 1-butanol. propanoic acid is more soluble in water than 1-butanol. propanoic acid is a better hydrogen bond donor than 1-butanol. propanoic acid forms hydrogen bonded dimers and 1-butanol does not. 1-butanol forms hydrogen bonded dimers and propanoic acid does not.

The bond energy for the van der waals bond between two helium atoms is 7.9×10−4ev. assuming that the average kinetic energy of a helium atom is (3/2)kbt, at what temperature is the average kinetic energy equal to the bond energy between two helium atoms