Question

Describe what quantity is measured and how the measurement is performed for each of the following techniques: (a) TGA, (b) DTA, (c) DSC, and (d) microthermal analysis.

Short answer

a. Name of quantity is the measurement of the mass of the analytes sample and the TGA technique works as a function of temperature.

b. Name of quantity is measuring the gap between the analyte the sample and the chemically stable inert reference and the DTA technique works as a function of temperature.

c. The name of quantity is the measurement of the heat difference between the analyte sample and the inert reference and the DSC technique used for the calculation of the heat difference.

d. Name of quantity is the scanning of thermally sensitive probe which occurs on the surface of the sample and the microthermal analysis technique works as a function of temperature and energy.

Step-by-step solution

Part (a) Step 1. Given information

Describe the name of quantity and the way it is measured by the TGA technique.

Part (a) Step 2. Explanation

TGA is a technique that is defined as the thermal analysis method, in which the physical and chemical properties of the material are measured. This technique is used for the measurement of the mass of the analyte's sample. This technique works as a function of temperature, which helps in the measurement of the quantity.

Part (b) Step 1. Given information 

Describe the name of quantity and the way it is measured by the DTA technique.

Part (b) Step 2. Explanation

The DTA is termed differential thermal analysis. This technique is used for the measurement of the gap between the analyte sample and the chemically stable inert reference or blank. This technique works as a function of temperature which helps to perform the measurement.

Part (c) Step 1. Given information 

Describe the name of quantity and the way it is measured by the DSC technique.

Part (c) Step 2. Explanation

The DSC technique is also termed differential scanning calorimetry. In this, the heat difference between the analyte sample and the reference sample is measured. The heat difference is calculated with respect to temperature. The heat or energy is transferred to the reference sample in the exothermic process while in the endothermic process, the energy or heat is transferred to the analyte sample.

Part (d) Step 1. Given information 

Describe the name of quantity and the way it is measured by the microthermal analysis technique.

Part (d) Step 2. Explanation

In microthermal analysis, scanning of the thermally sensitive probe occurs on the surface of the sample. In this, the electric energy is used to maintain the temperature constant on the probe which is measured and detected during the scanning process. The amount of energy required is less when the probe is near the region of the low thermal conductivity. Whereas, when the probe is near to the region of high thermal conductivity, it requires high energy to maintain the temperature.