Experiment Procedure, Part A.1. What the procedure for heating a metal to an exa

Question

Experiment Procedure, Part A.1. What the procedure for heating a metal to an exact but measured temperature? Experimental Procedure, Parts A.4, 5. a. When a metal at a higher temperature is transferred to water at a lower temperature, heat is inevitably lost to the calorimeter (Figure 25.4). Will this unmeasured heat loss increase or decrease the calculated value of the specific heat of the metal? Explain. see equation 25.5. b. Explain why the extrapolated temperature is used to determine the maximum temperature of the mixture rather than the highest recorded temperature in the experiment. See Figure 25.5 Experimental Procedure, Part B. Three student chemists measured 50.0 mL of 1.00 M NaOH in separate Styrofoam coffee cup calorimeters (Part B). Brett added 50.0 mL 1.10 HCl his solution of NaOH; Dale added 45.5 mL of 1.10 M HCl (equal moles) to his NaOH solution. Lyndsay added 50.0 mL of 1.00 M HCl her NaOH solution. Each student recorded the temperature change and calculated the enthalpy of neutralization. Identify the student who observes a temperature change that will be different from that observed by the other two chemists. Explain why and how (higher or lower) the temperature will be different.

Explanation / Answer

2a)

The calculated heat lost by the metal is = heat gained by the water

Calculated heat lost by metal is determined by the temperature increase of the water. If the calorimeter absorbs some of the heat, and we fail to account for that, then the smaller increase in the water temperature would lead you to under-calculate the heat lost by the metal. Now the calculated specific heat varies with the calculated heat lost. The calculated specific heat would be too low.

b) If we are doing a calorimeter experiment in which we have to measure T

We measure the temperatures over a period of time and plot a graph. But the maximum temperature is not that shown on the graph, because the calorimeter is not a perfect insulator. It is constantly losing heat to the room. So the extrapolated temperature is used to determine the maximum temperature of the mixture rather than the highest recorded temperature in the experiment.

Related Questions

Navigate

• Browse (All)
• Browse E
• Subjects

---

---

Integrity-first tutoring: explanations and feedback only — we do not complete graded work. Learn more.