What Reaction Could Be Occurring As The Na And K Surface Tarnishes
1. Sodium and potassium are the most frequently ecountered alkali metals, though rarely as the metal. Why these elements are rarely found as the metal? (Refer to the relative measurements tabulated in the form of electronegativities, ionization energies, or reduction potentials).
These are due to the fact that their outer most orbital (ns1 valence electron configuration) has tendency to lose electron very easily and make stable configuration. The single valence electron is relatively far from the nucleus, only weak attractions exist in the solid between delocalized electrons and the metal-ion cores. Such weak metallic bonding means that the alkali metal crystal structure can be easily deformed or broken down. This resulting both elements become …show more content…
What reaction(s) could be occurring as the Na and K surface tarnishes? Write balanced equations for each reaction you can imagine. Hint: Recall air is mae up of water vapour, nitrogen, and oxygen. Suggest why oxygen (found as O2 in the air we breathe) is more likely to react rather than nitrogen (N2).
The surface of Na and K could be tarnished because of reaction with oxygen. If Na or K is burned in air, the results are mainly formation of white sodium peroxide, Na2O2 and orange potassium superoxide, KO2.
2Na (s) + O2 (g) → Na2O2 (s)
K (s) + O2 (g) → KO2 (s)
Oxygen, O2 is more likely to react than nitrogen, N2 because the oxygen molecule has partially-filled in the p-orbital diagram. This makes it very reactive due to repulsion energy between the two unpaired electrons. While, nitrogen which has a stable structure (half-filled) than oxygen.
3. Small detonations and flames have been known to occur when Na or K metals react with water. Attempt to figure out what are the most probable reactions that can happen and write their balanced equations. Explain why detonations and flames are possible.
Na (s) + H2O (l) → NaOH (aq)+ H2 (g)
K (s) + H2O (l) → KOH (aq)+ H2 …show more content…
For instance, there were gas released (produce bubbles of gas or fizzing) during the reaction.
7. Do you think there might be something preventing the magnesium from reacting with water at room temperature? Do you think magnesium would react faster in hot water? Explain.
The oxide layer of magnesium prevents it from reacting with water at room temperature due to low activation energy. In hot water, magnesium reacts faster and vigorously as the kinetic energy of the reactants increases with a rise in temperature. This is because it has greater activation energy which is enough to broken down the insoluble layer of magnesium oxide due to its exposure to surrounding air.
8. What would you expect to happen if you placed sodium or potassium in an acidic solution? Would the reaction be faster or slower than that observed for magnesium?
If sodium or potassium is placed in an acidic solution, the reaction will be faster than that observed for magnesium. Also, practically this reaction will be violent due to the high reactivity of group 1 elements. The reaction is similar to the reaction with water, forming the melt salt plus hydrogen
These are due to the fact that their outer most orbital (ns1 valence electron configuration) has tendency to lose electron very easily and make stable configuration. The single valence electron is relatively far from the nucleus, only weak attractions exist in the solid between delocalized electrons and the metal-ion cores. Such weak metallic bonding means that the alkali metal crystal structure can be easily deformed or broken down. This resulting both elements become …show more content…
What reaction(s) could be occurring as the Na and K surface tarnishes? Write balanced equations for each reaction you can imagine. Hint: Recall air is mae up of water vapour, nitrogen, and oxygen. Suggest why oxygen (found as O2 in the air we breathe) is more likely to react rather than nitrogen (N2).
The surface of Na and K could be tarnished because of reaction with oxygen. If Na or K is burned in air, the results are mainly formation of white sodium peroxide, Na2O2 and orange potassium superoxide, KO2.
2Na (s) + O2 (g) → Na2O2 (s)
K (s) + O2 (g) → KO2 (s)
Oxygen, O2 is more likely to react than nitrogen, N2 because the oxygen molecule has partially-filled in the p-orbital diagram. This makes it very reactive due to repulsion energy between the two unpaired electrons. While, nitrogen which has a stable structure (half-filled) than oxygen.
3. Small detonations and flames have been known to occur when Na or K metals react with water. Attempt to figure out what are the most probable reactions that can happen and write their balanced equations. Explain why detonations and flames are possible.
Na (s) + H2O (l) → NaOH (aq)+ H2 (g)
K (s) + H2O (l) → KOH (aq)+ H2 …show more content…
For instance, there were gas released (produce bubbles of gas or fizzing) during the reaction.
7. Do you think there might be something preventing the magnesium from reacting with water at room temperature? Do you think magnesium would react faster in hot water? Explain.
The oxide layer of magnesium prevents it from reacting with water at room temperature due to low activation energy. In hot water, magnesium reacts faster and vigorously as the kinetic energy of the reactants increases with a rise in temperature. This is because it has greater activation energy which is enough to broken down the insoluble layer of magnesium oxide due to its exposure to surrounding air.
8. What would you expect to happen if you placed sodium or potassium in an acidic solution? Would the reaction be faster or slower than that observed for magnesium?
If sodium or potassium is placed in an acidic solution, the reaction will be faster than that observed for magnesium. Also, practically this reaction will be violent due to the high reactivity of group 1 elements. The reaction is similar to the reaction with water, forming the melt salt plus hydrogen