Question: Explain whether using solid NaOH pellets rather than aqueous NaOH would alter the enthalpy. If different, would it be higher or lower

My answer: Would the result be different since the aqueous NaOH would be able to quickly dissolve in water unlike solid NaOH which would take longer? Also, the enthalpy would then be lower for the solid pellets

Alter the enthalpy of what Everyone knows that dropping solid NaOH pellets into H2O is a HUGE exothermic reaction.

To determine whether using solid NaOH pellets instead of aqueous NaOH would alter the enthalpy, we need to consider the dissolution process. Enthalpy is a measure of the heat content of a system and can be influenced by changes in temperature, pressure, and the physical state of the substance.

When solid NaOH dissolves in water, it undergoes an exothermic process, meaning it releases heat. This is because energy is released when the attractive forces between water molecules are replaced by the attractive forces between water molecules and NaOH ions. In contrast, the dissolution of aqueous NaOH does not involve any solid-state NaOH, as it is already dissolved in water.

So, in the case of solid NaOH pellets, the dissolution process needs to occur before the full enthalpy change can be measured. This process will indeed take longer compared to using aqueous NaOH, where the enthalpy change can be directly measured. The slower dissolution of solid NaOH will not affect the magnitude of the enthalpy change but will delay its measurement.

However, as long as the amount of NaOH and water used remains constant, the enthalpy change for both solid NaOH and aqueous NaOH will be the same. Therefore, the enthalpy itself will not be altered by using solid pellets of NaOH. The enthalpy change represents the energy difference between the reactants and products, regardless of the physical state.

In conclusion, although the time required for the enthalpy change to be determined may be different for solid NaOH pellets compared to aqueous NaOH, the enthalpy itself remains the same.