A covalent bond is a form of chemical bonding between two non-metals, whereas ionic bonding is a bond between a metal and a non-metal.
Answer:
a free swimming larval stage in which a parasitic fluke passes from an intermediate host to another intermediate host
Answer:
Option 4
Explanation:
In water molecule, oxygen has -2 charge on it while the hydrogen has +1 charge and one atom of oxygen combines with two hydrogen atoms. A hydrogen need only two electrons to complete its octet (one electron is its own the second electron is shared by oxygen) and a oxygen needs 8 electrons (It has six of its own and two are shared by two hydrogen atom).
Hence, option 4 is correct
The melting point of a particular compound is fixed and it is an important identification of an unknown compound. The practice to determine the melting point of an unknown material In different ratio with a known material is important to get the exact melting point of the unknown material. In different ratio the melting point of the unknown material will be fixed as the melting point of a pure material doesn't depend on the ratio in which they are mixed with other material. To get the exact melting point it is always good to get the melting point twice in different ratio.