а)Be(OH)2 + Co2<span> →BaCO3 ↓ + H2O</span>
1) CH4 + Br2 (свет) ===> CH3Br + HBr
<span>2) CH3Br + NaOH(водн. р-р) ===> CH3OH + NaBr </span>
<span>3) CH3OH + CuO (температура) ===> Cu + H2O + HCHO </span>
<span>4) 5HCOH + 2KMnO4 + 3H2SO4 ===> 5HCOOH + 2MnSO4 + K2SO4 + 3H2O</span>
CO2 + BaO --> BaCO3
CO2 + Ba(OH)2 --> BaCO3 + H2O
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