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?
To estimate the amount of sodium acetate and vinyl needed to make a pocket warmer, you'll want to consider a few factors: the enthalpy of hydration, the desired temperature, and the heat capacity of the water and outer package.
1. Enthalpy of hydration: The enthalpy of hydration refers to the energy released or absorbed when a compound dissolves in water. In this case, you'll need to calculate the enthalpy of hydration for sodium acetate. You can find this information in thermodynamics or chemistry textbooks or online databases.
2. Number of moles: Once you have the enthalpy of hydration, you can calculate the number of moles of sodium acetate using the equation:
Enthalpy = number of moles * enthalpy of hydration
Rearranging the equation, you can solve for the number of moles:
Number of moles = Enthalpy / enthalpy of hydration
3. Amount of sodium acetate: To determine the amount of sodium acetate to use, you'll need to know its molar mass. This information is typically provided on the compound's safety data sheet (SDS) or can be found in chemical reference books or online sources. Multiply the molar mass by the number of moles calculated in step 2 to get the mass in grams.
4. Desired temperature: Decide on the temperature you want the pocket warmer to reach. The specific temperature will depend on personal preference and the purpose of the pocket warmer. Keep in mind that sodium acetate has a freezing point of around 58 degrees Celsius (136 degrees Fahrenheit), so heating it above this temperature is necessary.
5. Heat capacity of the water: The heat capacity of water is the amount of heat energy required to raise the temperature of water by a certain amount. Typically, the heat capacity of water is around 4.184 J/(g°C) or 1 cal/(g°C). Multiply this value by the mass of water to calculate the heat capacity.
6. Heat capacity of the outer package: The outer package of the pocket warmer will also have its heat capacity. This will depend on the material and size of the package. If the heat capacity of the outer package is significant, you'll need to factor it into your calculations. You can usually find the heat capacity of various materials online or in reference books.
By considering these factors and using the appropriate formulas, you can estimate the amount of sodium acetate and vinyl to use and determine the overall temperature of the pocket warmer at the height of the reaction.