Answer:- B- 
Explanations:- Sharing of electrons takes place between non metals and the bond formed by the sharing of electrons is known as covalent bond. In first choice we only have a zinc metal and so no sharing of electrons would be possible here.
In third choice we have NaCl. Na is a metal and Cl is a non metal. The property of metals is to transfer its valence electrons to the non metal and the bond formed is known as ionic bond. So, third choice is also not correct.
In choice B we have sulfate ion that has sulfur and oxygen atoms and both of these are non metals. So, sharing of electrons is present here between the S and O atoms and covalent bonds are formed.
So, choice B-
is the right answer.
<u>Answer:</u> From the given gases, the greatest rate of effusion is of 
<u>Explanation:</u>
Rate of effusion of a gas is determined by a law known as Graham's Law.
This law states that the rate of effusion or diffusion of a gas is inversely proportional to the square root of the molar mass of the gas. The equation given by this law follows:

It is visible that molar mass is inversely related to rate of effusion. So, the gas having lowest molar mass will have the highest rate of effusion.
For the given gases:
Molar mass of 
Molar mass of 
Molar mass of 
Molar mass of 
Molar mass of 
The molar mass of methane gas is the lowest. Thus, it will have the greatest rate of effusion.
Hence, the greatest rate of effusion is of 
Answer:
The higher the temperature the more water evaporates and that affects the convection process
Explanation:
Answer : The correct option is (A) Hydrogen region of the molecule.
Explanation :
As we know that the water molecule has two hydrogen atom and one oxygen atom. The hydrogen atom has partial positive charge and oxygen has partial negative charge.
In the charged plate, the negative attracts positive and positive attracts negative. So, the hydrogen atom attracted to the negative plate and the oxygen atom attracted to the positive plate.
When water molecule placed between oppositely charged metal plates which is positively charged, then the hydrogen atom which is positively charged attracted towards the negative plate.
<span>ANSWER:
Organic reactions proceed at a very SLOWER rate.
Reasoning:
</span><span>Organic reactions are chemical reactions involving organic compounds. They are less soluble</span> in water than inorganic compounds. Therefore, organic compounds react at a slower rate and produce a much more complex set of products than inorganic compounds.