Chemistry - Section 3

Answer: Option B

Explanation:

a. Fertilizers -----> 1. Constructive and destructive matter

b. Nuclear Bomb --------> 2. Cooking Gas

c. LPG -----------> 3. Curse of chemical reactions

d. Carbon------------> 4. Advanced process

Answer: Option C

Explanation:

Acetophenone is the organic compound with the formula C₆H₅−CO−CH₃. It is the simplest aromatic ketone. This colourless, viscous liquid is a precursor to useful resins and fragrances.

Acetophenone can be obtained by a variety of methods. In industry, acetophenone is recovered as a by-product of the oxidation of ethylbenzene, which mainly gives ethylbenzene hydroperoxide for use in the production of propylene oxide.

Answer: Option D

Explanation:

Seawater contains large amounts of dissolved ions and the four most concentrated metal ones which are magnesium, calcium, potassium and sodium are being commercially extracted today. However, all the other metal ions exist at much lower concentrations.

Answer: Option A

Explanation:

Dmitri Ivanovich Mendeleev was a Russian chemist and inventor. He formulated the Periodic Law, created his own version of the periodic table of elements, and used it to correct the properties of some already discovered elements and also to predict the properties of eight elements yet to be discovered.

Answer: Option B

Explanation:

The most important form of elemental phosphorus from the perspective of applications and the chemical literature is white phosphorus. It consists of tetrahedral P₄ molecules, in which each atom is bound to the other three atoms by a single bond.

This P₄ tetrahedron is also present in liquid and gaseous phosphorus up to the temperature of 800 °C (1,470 °F) when it starts decomposing to P₂ molecules

Answer: Option C

Explanation:

a. A Fatty Acid --------------------------> 4. Oil and fats

b. Potassium Hydroxide ------------> 1. Better Alkali

c. Non-ionic Surfactants -----------> 2. Process to make detergent

d. Neutralization ----------------------> 3. Process to make soap

Answer: Option B

Explanation:

Copper does not belong to the group 18 of the periodic table.

Inert gas or noble gas, any of the elements in Group 18 of the periodic table. In order of increasing atomic number they are: helium, neon, argon, krypton, xenon, and radon.

Answer: Option C

Explanation:

Allene and Propyne are examples of isomers containing different bond types. Allene contains two double bonds, whereas propyne contains one triple bond.

Answer: Option B

Explanation:

Fluorine is the lightest halogen and exists as a highly toxic pale yellow diatomic gas at standard conditions. As the most electronegative element, it is extremely reactive: almost all other elements, including some noble gases, form compounds with fluorine.

Answer: Option B

Explanation:

A non-luminous flame is colourless and is much hotter. A non-luminous flame undergoes complete combustion as it draws much more oxygen and gets much hotter. There are several "zones" within a non-luminous flame, and each zone has a different temperature.

The outermost zone of the flame is blue in colour and it is the hottest part. This is due to complete combustion.

The middle zone is moderately hot and is yellow in colour. This is because of partial combustion.

The innermost zone is the least hot and black in colour. This is due to the presence of unburned wax vapours.