MPSC PYQ

MPSC Rajyaseva 2021 GS Paper 1 — Question 66

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32 ग्रॅम मिथेन (रेणु वस्तुमान 16 g/mol) आणि 192 ग्रॅम ऑक्सिजन (रेणु वस्तुमान 32 g/mol) एकत्र मिसळले. हे दोन वायू जर एकमेकांशी रासायनिक प्रक्रिया करत नसतील तर मिथेन वायूचे मोल फ्रॅक्शन किती ? / 32 g of methane (molar mass 16 g/mol) is mixed with 192 g of oxygen (molar mass 32 g/mol). Presuming that these gases donot react with each other, what is the mole fraction of methane ?

1)0.25✓ Correct
2)6
3)0.167
4)4

Moles of methane = 32/16 = 2 moles. Moles of oxygen = 192/32 = 6 moles. Total moles = 2 + 6 = 8 moles. Mole fraction of methane = Moles of methane / Total moles = 2/8 = 0.25 (or 1/4).