UPSC CSE Prelims 1999 Q127 — Science & Technology PYQ

1999Q127·Science & Technology·Materials & Engineering

Consider the following statements:

I. Glass can be etched or scratched by diamond.

II. Glass can be etched or scratched by hydrofluoric acid.

III. Glass can be etched or scratched by aqua regia.

IV. Glass can be etched or scratched by concentrated sulphuric acid.

Which of these statements are correct?

UPSC CSE Prelims 1999 Q127 — Science & Technology PYQ with Answer

UPSC CSE Prelims 1999 Q127 — Science & Technology PYQ with Answer