Using the activity series (Table 4.5), write balanced chemical equations for the following reactions. If no reaction occurs, simply write NR. (b) zinc metal is added to a solution of magnesium sulfate
So in this equation we have zinc reacting with magnesium sulphate. Remember magnesium is in group 2A so it's +2, sulphate is SO42- so magnesium sulphate is MGSO4. So basically what we're looking here for is can zinc displace magnesium? This is known as a metal displacement reaction. Basically one metal is trying to kick out another metal so it can combine with the other ion. To figure this out we look at the chart, our activity series chart. So we're looking at zinc versus magnesium.
So zinc is trying to kick it out, so we have to look on this chart so zinc is here, zinc wants to kick out the magnesium. Where is magnesium? Magnesium is up here. Here we have a problem. The metal that is lower can not displace the metal that is higher up so since zinc is lower than magnesium, it can't displace magnesium. So we'd say here that this is no reaction. So again the only way a metal can displace another metal is if that metal is higher up on the activity series chart. Here zinc is lower so it won't be able to displace magnesium at all.