Yes, potassium can displace sodium.
Based on the reactivity series of metals, potassium is significantly more reactive than sodium. This difference in reactivity means that potassium is able to remove sodium from its compounds.
Understanding Reactivity
Metals are ranked in a reactivity series based on their tendency to lose electrons and form positive ions. The higher a metal is in the series, the more reactive it is. A more reactive metal can displace a less reactive metal from a solution of its salt or from molten salt.
Here's a simplified look at their relative positions:
- Potassium (K) - Higher Reactivity
- Sodium (Na) - Lower Reactivity
As the provided reference states, "considering the position of sodium and potassium in the reactivity series this can be seen that sodium is less reactive than potassium. Hence potassium will displace sodium from its salt."
Why Displacement Occurs
Since potassium is above sodium in the reactivity series, potassium atoms have a stronger tendency to lose electrons and become positive ions compared to sodium atoms. In a reaction where both are present in a suitable form (like a salt solution or molten salt), potassium can take electrons from the sodium ions, effectively turning the sodium ions back into neutral sodium atoms, while the potassium atoms become potassium ions.
For example, in a theoretical reaction with a sodium salt (like sodium chloride, NaCl), if potassium were added under suitable conditions (this reaction is highly vigorous and potentially explosive, especially with water present), the potassium could displace the sodium:
K + NaCl → KCl + Na
This equation represents a redox reaction where potassium is oxidized (loses electrons) and sodium ions are reduced (gain electrons).
Key Takeaways:
- Reactivity Series: Potassium is higher than sodium.
- Relative Reactivity: Potassium is more reactive than sodium.
- Displacement Rule: A more reactive metal can displace a less reactive metal from its salt.
- Conclusion: Potassium can displace sodium from its salts.
Understanding the reactivity series helps predict the outcome of many chemical reactions involving metals.
