2CH3OH + 2Na = 2CH3ONa +H2

m(CH3OH)= 128 g

m(Na)= 115 g

M(CH3OH)= 32 g/mol

M(Na)= 23 g/mol

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m(CH3ONa)- ?

M(CH3ONa)=54 g/mol;

2CH3OH + 2Na = 2CH3ONa +H2. =>

  m(CH3ONa) / 2M(CH3ONa) = min {m(CH3OH) / 2M(CH3OH); m(Na) / 2M(Na)}.

         m(CH3OH) : 2M(CH3OH) = 128:64 =2;

         m(Na) : 2M(Na) = 115:46 =2,5; 2,5 > 2  ==>

m(CH3ONa) / 2M(CH3ONa) = m(CH3OH) / 2M(CH3OH);

m(CH3ONa) = 2M(CH3ONa) * m(CH3OH) / 2M(CH3OH) 

m(CH3ONa) = 2 * 54 * 128 / 64 = 216 g.

________________
СН3ОН + НBr = СН3Br + H2O; 

C3H7OH + HBr =\=>

M(СН3ОН) = 32 g/mol

M(C3H7OH) = 60 g/mol

m(СН3ОН) + m(C3H7OH) = 124 g

n(HBr) = 3 mol  

СН3ОН + НBr = СН3Br + H2O

n(СН3ОН) = m(СН3ОН) / M(СН3ОН) = n(HBr) = 3 : 1 ==>

m(СН3ОН) = M(СН3ОН) * n(HBr) = 32 * 3 = 96 g

m(C3H7OH) = 124 - 96 = 25 g

m(СН3ОН) = 96 g m(C3H7OH) = 25 g