Why do we maintain temperature around 105 OC in soil moisture determination?

A2A! As we know 70 degree C is the maximum temperature to make volatilize. But in case soil we oven dry it between 105–110 centigrade . Because soil carries heavy moisture content while excavated.

Why should soil samples be dried at 105 degrees?

As per ASTM D2216, the drying temperature is about 105 c. In order to reduce the degree of dehydration of gypsum in those materials containing gypsum, or to reduce decomposition in highly organic soils, it may be desirable to dry these materials at 60°C or in a desiccator at room temperature.

Why do you think it is required to oven dry the soil at a temperature of 110 C as per ASTM standard?

Normally, the water content of a soil is measured by oven drying the soil at 110 ºC. This temperature is used because it is high enough to evaporate all the water present in the pore spaces of the soil but is not so large that it drives water out of the structure of most minerals.

Can you remove the absorbed water by oven drying at 105 degrees C?

All Answers (5) It is generally done at 105 degree centigrade. Dear Debra, (1) Moisture content determination in soil by oven-drying method is based on removing soil moisture by oven-drying a soil sample until the weight remains constant.

Why do we need to determine the moisture content of soil?

Knowing the soil moisture status enables highly efficient irrigation, providing the water as and when required, and eliminating the wasteful use of water when irrigation is not needed. Roots can penetrate soil so that the plant can anchor itself and also so that it can access the nutrients and water stored in the soil.

What are the reasons for carrying out moisture content test on soils?

In soil science, hydrology and agricultural sciences, water content has an important role for groundwater recharge, agriculture and soil chemistry. If the moisture content of a soil is optimum for plant growth, plants can readily absorb soil water. Not all the water, held in soil, is available to plants.

What temperature do you dry soil?

For total carbon measurements (e.g. element analyzer) soils are usually dried at 40°C until constant weight. For soil water determination soils are heated up to 105 or even 110°C.

Where and at what temperature should you dry samples?

Drying is best accomplished by spreading each sample on paper to air dry at room temperature. Do not oven dry the samples.

Why soil moisture content determination should be oven dried?

Rightly said, in the thermo-gravimetric method, the measurement of water content in soil sample is based on the loss in the weight of moist soil after drying, so there is no need of air drying. Soil sample is commonly dry in an oven at 105 degree Celsius for 24 hours to a constant weight.

What is the primary purpose of the drying oven in the chemistry lab?

A Drying oven is designed to remove moisture from the oven chamber so to dry the samples as quickly as possible. The drying oven process introduces fresh dry air to the chamber and expels the warm moist air simultaneously allowing to rapidly dry the samples. A drying oven provides high performance drying and heating.

Why do we oven dry soil?

You are to determine the dissolved organic matter, then why will you need to go for soil drying on an oven. Drying the soils on oven may cause the loss of the organic matter even at low temperature (about 60 C). Air dried samples are sufficient to provide the dissolved organic matter.

Which drying method is the best?

Air drying

• Oven drying is a lengthy process that takes 2 to 3 times longer than an electric dehydrator.
• Commercial or homemade electric dehydrators provide the most reliable and consistent results, often without pretreatment, because of the controlled temperature and air flow.