BPSC – Combined Competitive Examination · ಪ್ರಶ್ನೆ 10
In the context of lab-grown diamonds (LGDs), what is used as the starting carbon material ('seed')?
ಉತ್ತರ ತೋರಿಸು ಮತ್ತು ವಿವರಣೆ
ಉತ್ತರ: (C) Graphite
ವಿವರಣೆ
Lab-grown diamonds must start from carbon; in the HPHT method graphite is the carbon source (CVD uses a thin diamond seed plate with methane).
- (A) ತಪ್ಪು
Wrong: aluminium oxide; contains no carbon.
- (B) ತಪ್ಪು
Wrong: silicon carbide; a diamond simulant.
- (C) ಸರಿ
Correct: graphite, a form of carbon, is converted to diamond under high pressure and temperature.
- (D) ತಪ್ಪು
Wrong: zirconium dioxide; a diamond simulant.