Practice MCQ Questions and answers on Chemistry-GK

Type Metals is the substance which does not expand on going from liquid to solid state. Type metal is nothing but an alloy of lead, tin, and antimony, used for casting type.

Ethylene glycol (IUPAC name: ethane-1,2-diol) is an organic compound widely used as an automotive antifreeze and a precursor to polymers. In its pure form, it is an odorless, colourless, syrupy, sweettasting liquid. Ethylene glycol is toxic, and ingestion can result in death. Due to its low freezing point ethylene glycol resists freezing. A mixture of 60% ethylene glycol and 40% water freezes at -45 degree C (-49 degree F). Diethylene glycol behaves similarly. It is used as a deicing fluid for windshields and aircraft. The antifreeze capabilities of ethylene glycol have made it an important component of vitrification (anticrystallization) mixtures for low-temperature preservation of biological tissues and organs.

Gold is the heaviest metal among the following.

Magnesium metal is used for the preparation of the wire of flash bulb.

Chlorophyll is the green pigment found in most plants, which is responsible for light absorption to provide energy by photosynthesis. Chlorophyll contains magnesium ion.

Tungsten is the hardest metal among the following.

Nichrome is a non-magnetic alloy of nickel, chromium, and often iron, usually used as a resistance wire. Patented in 1905, it is the oldest documented form of resistance heating alloy. A common alloy is 80% nickel and 20% chromium, by mass, but there are many others to accommodate various applications. It is silvery-grey in colour, is corrosion-resistant, and has a high melting point of about 1400 degree C (2552 degree F). Due to its relatively high electrical resistivity and resistance to oxidation at high temperatures, it is widely used in electric heating elements, such as in hair dryers, electric ovens, soldering iron, toasters, and even electronic cigarettes. Typically, Nichrome is wound in coils to a certain electrical resistance, and current is passed through to produce heat.

Gold is always found in free-state in nature.

Philosopher’s Wool is Zinc oxide.

Mercury has least melting point.