SSC General Science & Technology Sample Paper NCERT Sample Paper-1

  • question_answer
    During elections, a permanent, chemical mark is put at the base of the nail of index finger while exercising your franchise. This mark is not seen after two months or so because:

    A)  It is worn out by constant washing with soap and water.

    B)  Constant contact of the hands with hard water corrodes the mark

    C)  The formation of new nail, forcibly removes the old one.

    D)  It is gradually oxidised by tannin and caffein that we ingest in tea and coffee respectively.

    Correct Answer: C

    Solution :

    [c] Election ink, electoral stain or phosphoric ink is a semi-permanent ink or dye that is applied to the forefinger (usually) of voters during elections in order to prevent electoral fraud such as- double voting. It is an effective method for countries where identification documents for citizens are not always standardised or institutionalised. Electoral stain typically contains a pigment for instant recognition, and silver nitrate which stains the skin on exposure to ultraviolet light, leaving a mark that is impossible to wash off and is only removed as external skin cells are replaced. Industry standard electoral inks contain 10%, 14% or 18% silver nitrate solution, depending on the length of time the mark is required to be visible. Although normally water-based, electoral stains occasionally contain a solvent such as alcohol to allow for faster drying, especially when used with dipping bottles, which may also contain a biocide to ensure bacteria aren't transferred from voter to voter.

You need to login to perform this action.
You will be redirected in 3 sec spinner