The molecular mass of methyl ethanoate is 74.1 amu . calculate the molecular mass of propanoic acid, an isomer of methyl ethanoate. express your answer with the appropriate units.

Isomers are the compounds having same molecular formula but different structural formula. 

Since, molecular formula is isomers are same, they have same mass.

Now, methyl ethanoate is  an isomer of propanoic acid, hence they have same mass.

∴ Molecular mass of propanoic acid = 74.1 amu or 74.1 g/mol

The activity series is shown in the attached picture. if the element is below the other, then you can displace the other. following the activity series as a guide, the reactions are as follows: nickel and aluminum chloride3 ni + 2 alcl₃  → 3 nicl₂ + 2 albarium and copper bromideba + cubr  →  no reaction because cu is less oxidizable than bapotassium nitrate and aluminum3 kno₃ + al  → al(no₃)₃ + 3 ksodium phosphate and zincnaso₄ + zn  → znso₄ + na