Kimyo-7 Savolnoma 1-chorak 1-nazorat ishi uchun Kimyo fani nimani o’rganadi? 2

KIMIYO – 7. II – chorak. 4 – nazorat ishi. 1-variant
1. SO₂ ning tarkibida necha foiz kislorod borligini hisoblang. A) 25% B) 50% C) 53% D) 66%
2. 18 g suvning parchalanishidan hosil bo’ladigan kislorodning massasini hisoblang.
A) 2 g B) 8 g C) 16 g D) 18g
3. 60% “Mg” va 40% “O” dan iborat moddaning molekulyar formulasini aniqlang.
A) MgO B) MgO₂ C) Mg₂O D) Mg₂O₃
4. Ozondan kislorod hosil bo’lish reaksiyasi 3O₂ = 2O₃ – 289 kJ tarzida ifodalanadi. Shunga ko’ra 4 mol ozon hosil bo’lishi uchun qancha issiqlik yutilishini hisoblang.
A) 144,5 kJ B) 289 kJ C) 578 kJ D) 2890 kJ
5. Vazni 80 kg bo’lgan insonning tanasidagi kislorod miqdori necha kg ni tashkil etishini hisoblang.
A) 39 kg B) 52 kg C) 55 kg D) 63 kg