To make a pocket warmer from sodium acetate and vinyl, how do you estimate how many grams to use? to work out the 'q' is it the heat capacity of the water it is dissolved in that you use? What temperature do you want it to get to and how do you factor in the heat capacity of the outer package?
Calculate the enthalpy of hydration, no of moles, amount of sodium acetate to use and over all temperature at the height of the reaction. Please help me with this one? It is all to do with Thermodynamics and Clausis-Clapeyron.
This is not research, Jannis, this is getting some to do it for you!!!!
To estimate how many grams of sodium acetate to use in order to make a pocket warmer, you would need to consider several factors such as the desired temperature, the heat capacity, and the heat transfer properties of the outer package. Here's a step-by-step guide to help you calculate the necessary parameters and quantities:
1. Determine the desired temperature: Decide on the temperature you want the pocket warmer to reach. Let's assume you want it to reach around 50°C.
2. Calculate the enthalpy of hydration: The enthalpy of hydration refers to the heat energy released or absorbed when a substance dissolves in water. In this case, you need to calculate the enthalpy of hydration for sodium acetate. This can be found in reference tables or online resources.
3. Calculate the number of moles: Next, convert the desired temperature change into an actual heat value. The equation q = mcΔT can be used, where q is the heat energy absorbed or released, m is the mass of the sodium acetate, c is the heat capacity of the water, and ΔT is the temperature change. Rearrange the equation to solve for mass (m):
m = q / (cΔT)
4. Determine the heat capacity of the water: The heat capacity of water is approximately 4.18 J/g°C. However, if you're dissolving the sodium acetate in a different liquid, you would need to use the specific heat capacity of that liquid instead.
5. Consider the heat capacity of the outer package: The heat capacity of the outer package will depend on the material it's made of. Different materials have different heat capacities. You can find heat capacity values for common materials online. Multiply the heat capacity by the mass of the package to get the heat capacity of the outer package.
6. Optimize the sodium acetate amount: To ensure the pocket warmer reaches the desired temperature, you might need to iterate and adjust the amount of sodium acetate used. Start with a reasonable estimate based on initial calculations and then conduct a trial and error process to fine-tune the amount used.
7. Factor in Clausius-Clapeyron equation: The Clausius-Clapeyron equation is used to calculate the vapor pressure of a substance at different temperatures. While it's not directly related to estimating the amount of sodium acetate to use, it could be useful in understanding the behavior of the pocket warmer.
Remember that the calculations provided are approximate and the actual results may differ due to various factors such as heat losses to the surroundings and other external conditions.