As water is boiled, kinetic energy causes<span> the </span>hydrogen bonds to break<span> completely and allows water molecules to escape into the air as gas (steam or water vapor). When water freezes, water molecules form a crystalline structure maintained by </span>hydrogen bonding<span>. Solid water, or </span>ice<span>, is less dense than liquid water.</span>
Explanation:
<u>Polar covalent bonding is the type of the chemical bond in which the pair of the electrons is unequally shared between the two atoms.</u> As a result, the atom with higher value of electronegativity acquires a slightly negative charge and the atom with lower value of electronegativity acquires a slightly positive charge.
In the molecule of 
, the bond which is closest to ionic end of bond spectrum is <u>N-H bond</u> because the nitrogen atom is more electronegative than hydrogen and is ionic in nature.
In the molecule of 
, the bond which is closest to ionic end of bond spectrum is <u>no one</u> because there is not much difference between carbon and hydrogen for the bond to be said as ionic.
In the molecule of 
, the bond which is closest to ionic end of bond spectrum is <u>O-H bond</u> because the oxygen atom is more electronegative than hydrogen and is ionic in nature.
Answer: Do want the experiment done or help of the experiment
Answer: Option (4) is the correct answer.
Explanation:
A mixture is defined as a substance that contains two or more different substance that are physically mixed with each other.
If solute particles are evenly distributed in a solvent then it is known as a homogeneous mixture.
For example, salt dissolved in water is a homogeneous mixture.
If solute particles are unevenly distributed into the solvent then it is known as a heterogeneous mixture.
For example, sand in water is a heterogeneous mixture.
Thus, we can conclude that the statement a mixture must contain at least two different substances, is correct about mixtures.
