a) 2CH3-CH2-CH2-OH+2K--->2CH3-CH2-CH2-OK+H2
b) 2CH3-CH2-CH2-OH+Mg--->(CH3-CH2-CH2-O)2Mg+H2
c) 2CH3-CH2-CH2-OH+CuO--->(CH3-CH2-CH2-O)2Cu+H2O