CO2 is the abreviation for carbon dioxide.
Answer:
Gneiss forms by regional metamorphism from both high temperature and pressure. Quartzite and marble are the most commonly used metamorphic rocks.
B for sure, considering iron oxide is just fancy for rust.
A molecule has an empirical formula of ch, and its molar mass is known to be 26 g/mol and the molecular formula is C₂H₂ ethyne
Molecular formula of compound is (CH)n and the given molar mass is 26g/mol
Molar mass of (CH)n, C=12=n(12+1)=13n
So 13n and n=2
=13×2=26 and given molar mass is also 26g/mol
So here two carbon and two hydrogen so molecular formula is C₂H₂ and name is ethyne
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