Answer:
A:UNDERSTANDING CONCEPTS PART A 13) Which of the following is an example of periodicity? A) eating breakfast
Water can't cool at a single temperature. It must start at a higher temperature, and drop to a lower temperature in order to cool. Unless we know the other temperature, there is no way to calculate the amount of thermal energy released.
Answer:
Energy, 
Explanation:
It is required to find the energy of an electromagnetic wave with a frequency of
. The energy of a wave in terms of its frequency is given by :

= frequency of em wave

So, the energy of an electromagnetic wave is 
Answer:
The proton remains the same.
Explanation:
Oxidation is simply defined as the loss of electron(s) during a chemical reaction either by an atom, molecule or ion.
Oxidation is strictly on the transfer of electron(s) and not proton.
A metal that undergoes oxidation still has its protons intact otherwise it will not be called the ion of the metal since atomic number is called the proton number.
Sodium (Na) undergoes oxidation as follow:
Na —> Na+ + e-
Na is called sodium metal.
Na+ is called sodium ion.
Na has 11 electrons and 11 protons
Na+ has 10 electrons and 11 protons
From the above illustration, we can see that the protons of Na and Na+ are the same why their electrons differ because Na+ indicates that 1 electron has been loss or transferred.
Answer: Option (A) is the correct answer.
Explanation:
A covalent bond is formed when there occurs sharing of electrons between atoms.
For example, in hydrogen atom there is one electron in its orbit and in a chlorine atom there is 7 valence electron. So, in order to attain stability both hydrogen and chlorine share electrons when they come close to each other.
Whereas except hydrogen and chlorine rest of the given atoms will form ionic bond, that is, bond formed by transfer of electrons.
Thus, we can conclude that a pair of hydrogen and chlorine will form a covalent bond.