20 verified questions · ~18 minutes · answer key checked against the official NTA final key across multiple sources. Text-only questions (diagram-based excluded until they can be shown properly).
The element that does not belong to the same period of the remaining elements (modern periodic table) is:
Heat treatment of muscular pain involves radiation of wavelength of about 900 nm. Which spectral line of H atom is suitable for this? Given: Rydberg constant R_H = 10⁵ cm⁻¹, h = 6.6 × 10⁻³⁴ J s, c = 3 × 10⁸ m/s
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