Chemistry - Study Mode

[#871] Which one of the following elements exhibits the greatest tendency to lose electrons ?
Correct Answer

(B) Lithium

Explanation

Solution: Alkali metals such as Lithium are the most electropositive elements in the periodic table. As alkali metals have low ionization energies, they have a great tendency to lose electrons forming uni-positive ions.

[#872] Which one is heaviest naturally occurring element of the periodic element?
Correct Answer

(D) Uranium

Explanation

Solution: The heaviest naturally stable element is uranium, but over the years physicists have used accelerators to synthesize larger, heavier elements. In 2006, physicists in the United States and Russia created element 118.

[#873] Petroleum is a mixture of
Correct Answer

(B) Hydrocarbons

Explanation

Solution: Petroleum is a complex mixture of hydrocarbons that occur in Earth in liquid, gaseous, or solid form.

[#874] Which of the following contains high content of lead?
Correct Answer

(C) High octane fuel

Explanation

Solution: A high-octane-rated fuel, such gasoline contains lead. Straight-run gasoline is distilled directly from crude oil. Once the leading source of fuel, its low octane rating required lead additives. Most countries have phased out leaded fuel. Different additives have replaced the lead compounds. The most popular additives include aromatic hydrocarbons, ethers and alcohol (usually ethanol or methanol). Lead used to be added to petrol and this was the source of high levels of lead in the air.

[#875] Piped Natural Gas (PNG) is used for
Correct Answer

(D) Cooking

Explanation

Solution: LPG is Liquefied Petroleum Gas and PNG is Piped Natural Gas. LPG is supplied in liquid form just as the name suggests in cylinders whereas PNG is supplied through a pipeline. LPG is used as a fuel in heating appliances and vehicles, where as PNG is used for cooking (gas stoves) and heating water (gas geysers).