Which reactants will NOT generate a gaseous product?
1. Zn + HCl
2. NaOH + NH4Cl
3. CaCO3 + HCl
4. Na2CO3 + CaCl2
5. Na + H2O

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I'm not sur i'm sorry

Melting increases as mass increases. since alkanes are not branched molecular structures, the one with the heavier mass will have higher melting point.  octane's mp > butane's mp

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