“Lewis super-acids” | UPSC Current Affairs

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Context

Researchers at the Paderborn University, Germany have reported being able to make a unique class of catalysts – used in chemistry to accelerate reactions – called “Lewis super-acids”.

About “Lewis super-acids”

Named for the chemist, G N Lewis, Lewis super-acids derive from Lewis acids.
A Lewis acid is any substance, such as a Hydrogen ion (H+) that can accept a pair of nonbonding electrons.
In other words, a Lewis acid is an electron-pair acceptor. A Lewis base is any substance, such as the OH- ion, that can donate a pair of nonbonding electrons. A Lewis base is therefore an electron-pair donor.
Because Lewis acids add electron pairs, they are often used to speed up chemical reactions.
Lewis superacids are stronger than antimony pentafluoride -- the strongest Lewis acid -- and can break even the toughest bonds. Breaking strong, chemical bonds requires highly reactive substances.
Because they are so reactive, they are hard to manufacture.
Being able to make these super acids, enables non-biodegradable fluorinated hydrocarbons, similar to Teflon, and possibly even climate-damaging greenhouse gases, such as sulphur hexafluoride, to be converted back into sustainable chemicals.

PRACTICE QUESTION

Q) Which of the following statements is/are correct?

a. A Lewis acid is any substance, such as a Hydrogen ion (H+) that can accept a pair of nonbonding electrons.

b. Because Lewis acids add electron pairs, they are often used to speed up chemical reactions.

I. Only a

II. Only b

III. Both a and b

IV. Neither a nor b

Answer: Option III