Chemistry Test - 14

When aldehydes and ketones having α hydrogen atoms are treated with dilute alkali, two molecules of the carbonyl compound undergo condensation. The product is β hydroxy aldehyde known as aldol or ketone. This reaction is called aldol condensation. The term aldol is derived from the combination of two words aldehyde and alcohol, the two functional groups present in the product. The products of aldol condensation when treated with dilute acids undergo dehydration leading to the formation of alpha, beta-unsaturated aldehydes, and ketones. Aldehydes not having alpha hydrogen fail to give aldol condensation. The aldol condensation takes place via a carbanion formation with the loss of α hydrogen. The aldol of acetaldehyde is intermolecular aldol and requires two molecules of acetaldehyde.

The reaction is:

The product formed is 3 hydroxy butanal. On further dehydration, it will form Crotonaldehyde.

So, the aldol condensation of acetaldehyde results in the formation of

Ozone (O₃), or trioxygen, is a triatomic molecule consisting of three oxygen atoms. Ozone is diamagnetic, which means that its electrons are all paired.

Ozone, O is not a linear molecule. Actually, it is bent with an angle that is a little less than 120°. Ozone has fewer lone pairs than water, thus a larger angle between bonds.

Fluorine (\(\ce{F2}\)) is an univalent poisonous gaseous halogen, it is pale yellow-green and it is the most chemically reactive and electronegative of all the elements.Fluorine readily forms compounds with most other elements, even with the noble gases krypton, xenon and radon. It is so reactive that glass, metals, and even water, as well as other substances, burn with a bright flame in a jet of fluorine gas.

The correct order of reducing property of dioxides are\(\mathrm{SO}_{2}>\mathrm{SeO}_{2}>\mathrm{TeO}_{2}\).

The tendency of these group \(16\) elements to be in their higher oxidation state decreases down the group. That means, the tendency of the elements getting oxidized decreases down the group, and thus reducing property decreases from \(\mathrm{S}\) to \(\mathrm{Te}\).

We have to find the equivalent conductivity of a solution, which can be called the conductivity of a substance per gram

The equivalent of the same substance. This can be written as:

Equivalent conductivity \(=\frac{\text { conductivity }}{\text { gram equivalent }}\)

Now, we know that one gram equivalent of a substance is the number of gram equivalents per unit volume.

Gram equivalents \(=\frac{\text { No. of gram equivalents }}{\text { Volume }}\)

Here, we will consider the volume to be in \(m^{3}\) as it is the same as the volume in liters which is regularly considered to

Calculate the gram equivalents. Thus, taking the units for the gram equivalent:

Gram equivalents \(=\frac{g \text { equiv }}{m^{3}}\)

Substituting these units in the formula for equivalent conductivity we get,

Equivalent conductivity \(=\frac{\frac{S}{m}}{\frac{g \text { equiv }}{m^{3}}}\)

Now solving and simplifying, we get,

Equivalent conductivity \(=\frac{S}{m} \times \frac{m^{3}}{g \text { equiv }}\)

Equivalent conductivity \(=\frac{S m^{2}}{g \text { equiv }}\)

Equivalent conductance \(=\mathrm{cm}^{2} gm\) equiv \(^{-1}\)

\(M _{ net }=\frac{ M _{1} V _{1}+ M _{2} V _{2}}{ V _{1}+ V _{2}}\)

Total millimoles of solute\((M _{1} V _{1}+ M _{2} V _{2})=480 \times 1.5+520 \times 1.2\)

\(=720+624=1344\)

Total volume \( (V _{1}+ V _{2})=480+520=1000\)

Molarity of the final mixture \(=\frac{1344 }{1000}\)

\(=1.344 ~M\)

Hydrocarbons having single bonds are known as saturated hydrocarbon.

Saturated hydrocarbons are known as an alkane. These are also known as paraffin. Unsaturated hydrocarbons are having double or triple bonds i.e., alkenes and alkynes. A Saturated hydrocarbon is a hydrocarbon in which all the carbon-carbon bonds are single bonds.

B-form DNA is the common form of DNA exists under normal physiological condition. The double strands of B-DNA run in opposite directions. In a DNA molecule, the two strands are not parallel but intertwined with each other. Each strand looks like a helix.This structure, also known as the B form, the helix makes a turn every\(3.4 \mathrm{~nm}\).

The defects in which the stoichiometry of a crystal is not affected, are called stoichiometric defects. Thus, in such defects, the ratio of positive and negative ions are the same as indicated by a chemical formula of the compound. The compounds in which the number of positive and negative ions are exactly in the ratios indicated by their chemical formulae are called stoichiometric compounds. The defects that do not disturb the stoichiometry (the ratio of numbers of positive and negative ions) are called stoichiometric defects.

BeH₂, MgH₂ is the pairs of hydrides that are polymeric in nature. Dihydrogen will combine with almost all elements, except Noble gases under certain reaction conditions forming binary compounds that are popularly called hydrides and these hydrides can be expressed as EHx (e.g., CaH₂) or EmHn (e.g.,B₂H₆) where ‘E’ is the symbol of the element.