Chemistry MCQs

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Hydrocarbons are organic compounds containing carbon and hydrogen and found in crude oil and natural gas. The term petroleum is used as a common denotation for crude oil (mineral oil) and natural gas, i.e., the hydrocarbons from which various oil and gas products are made.

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Chewing gum was made of a substance called chicle mixed with flavorings. Chicle is a latex sap that comes from the sapodilla tree (native to Central America).

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Because of their high acidity, phenols are often called carbolic acids. Phenol is an aromatic organic compound with the molecular formula C₆H₅OH.

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Sodium Hydroxide is used to cause a reaction called saponification to create soap. Sodium Hydroxide is completely safe after it has been combined with other constituents to create an effective, safe, and diverse cleaning agent known as soap.

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The reason that it is paramagnetic is because the oxygen molecule has two unpaired electrons. Electrons not only go around the atom in their orbitals, they also spin, which creates a magnetic field. Unpaired electrons spin in the same direction as each other, which increases the magnetic field effect.

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Aufbau principle states that ‘in the ground state of the atom, the orbitals are filled in order of their increasing energies, starting with the orbital of lowest energy.’ The word aufbau is German word which means building up. The increasing order of energy and hence that of filling of orbitals is as follows: 1s, 2s, 2p, 3s, 3p, 4s, 3d, 4p, 5s, 4d, 5p, 6s, 4f, 5d, 6p.

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The electron was the first fundamental particle that was discovered. The credit for the discovery of the electron goes to J.J. Thomson based on his experiments carried out in a discharge tube. The discovery of negatively charged electron was later followed by the experiment conducted by Robert Millikan in 1909 to determine the quantity of charge on an electron.

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99.985% of hydrogen atoms contain only one proton. This isotope is called protium( 1H1). Rest of the percentage of hydrogen atom contains two other isotopes, the one containing 1 proton and 1 neutron is called deuterium (1D2, 0.015%) and the other one possessing 1 proton and 2 neutrons is called tritium (1T3 ). The latter isotope is found in trace amounts on the earth.

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Fertilizers provide three primary nutrients: Nitrogen (N), Phosphorus (P) and Potassium (K). Nitrogen supports vegetative growth. Phosphorus improves roots and flowering. Potassium strengthens resistance to environmental assaults, from extreme temperatures to pest attacks. Urea is the most important nitrogenous fertilizer in the market, with the highest Nitrogen content (about 46 per cent). It is a white crystalline organic chemical compound. Urea is neutral in pH and can adapt to almost all kinds of soils. It is a waste product formed naturally by metabolizing protein in humans as well as other mammals, amphibians and some fish. Urea is widely used in the agricultural sector both as a fertilizer and animal feed additive. More than 90% of world production of urea is destined for use as a nitrogen-release fertilizer. Urea has the highest nitrogen content of all solid nitrogenous fertilizers in common use.

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A rectified spirit, rectified alcohol, or neutral spirit is highly concentrated ethanol which has been purified by means of repeated distillation, a process that is called rectification. It typically contains 95% alcohol by volume (ABV). Rectified spirits are used in mixed drinks, in the production of liqueurs, for medicinal purposes, and as a household solvent.