Answer:
The answer is surface tension.
Explanation:
The high surface tension helps the paper clip - with much higher density - float on the water. The cohesive forces between liquid molecules are responsible for the phenomenon known as surface tension. hope this helps :)
C is incorrect. I has 21 PROTONS in its nucleus. Not neutrons.
69. The student's skin was obviously warmer than the initial temperature of the bracelet. According to the second law of thermodynamics, heat transfers from a higher temperature to a lower temperature hence heat transfers from the student's skin to the bracelet warming up the bracelet.
70. moles of copper=mass of copper/molar mass of copper
=30.1g/(63.55g/mol)= 0.4736 moles Cu
71. Delta H( heat released) = mCp(deltaT) = 30.1g(0.385 J/gK)(33-19)K = 162.23J
72. Copper is chemically less active than iron.
Converting a liquid to a gas is evaporation.
