You can put a known amount sodium into some sort of time release mechanism such as a pill made from soluble material. Then you can place the sodium into a calorimeter with a known mass of water and record the temperature change the water undergoes during the reaction. Then you can use the equation q(water)=m(water)c(water)ΔT to find the amount of heat absorbed by the water. since the amount of heat absorbed by the water is the amount of heat released from the sodium, q(sodium)=-q(water). Than you can use the equation q(sodium)=m(sodium)c(sodium)ΔT and solve for c(sodium)
I hope this helps and feel free to ask about anything that was unclear in the comments.
Temperature is a measurement of average kinetic energy of the particles in a sample which means that the sample with the highest temperature has the highest average kinetic energy of the particles.
That being said the answer would be 4) 10 mL of H2O (l) at 35 degrees Celsius since that sample has the largest temperature.
I hope this helps. Let me know if anything is unclear.
Explanation:
Here are the answers. Do note that I had to convert the enthalpy to joules and temperature to Kelvin to make the unit for entropy work out.
I would say physical, because a physical change is affecting the form of a chemical substance, but not it's chemical makeup.
The answer to the question is- Fe2O3
