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.
Answer:
The atom will become a new element.
Explanation:
You take the moles divided by the liters to get the molarity.
Answer:
Two water molecules contain 4 hydrogen atoms and 2 oxygen atoms. A mole of water molecules contains 2 moles of hydrogen atoms and 1 mole of oxygen atoms.
Explanation:
