Answer:
The sample a which is solid at 20°C is "Iodine"
The sample b which is liquid at 20°C is "Bromine"
The sample c which is gas at 20°C is "Chlorine"
Explanation:
Iodine : It starts melting at 113.7°C, so the solid sample found is the iodine. Iodine is present in both solid as well as in vapor state. Basically it is kept in closed jars. Only when it reaches the temperature above the melting point is starts melting.
Bromine: It is a non metallic element that is present in the liquid state, being a member of halogen group. It is heavy, mobile and dangerous reddish brown liquid. It is corrosive in nature, when comes in contact with human tissue and causes irritation in eye when comes in contact with its vapor.
Chlorine: In room temperature it is gas, as it has weak intermolecular interaction which fails to keep the molecules closely attached.
The presence of inorganic molecules is the meteorite condition in space similar to what was likely present in Earth's early atmosphere.
The earth initial atmosphere in its early form was too reducing and it was made up entirely of gases such as carbon monoxide, ammonia, methane, nitrogen and other gases.
This atmosphere did not have free oxygen, since it was the result of the mixture of metals, hydrogen and other chemical elements.
The high temperatures, ultraviolet rays and electrical discharges in the early atmosphere would have caused chemical reactions of the elements to form primitive organic molecules.
Meteorites are fragments of solid matter that contain a record of the chemical substances that existed in the early Solar System.
The most predominant gases still found in the space are hydrogen and helium.
Therefore, we can conclude that hydrogen and the presence of inorganic molecules are the initial elements that make up the Earth's early atmosphere and that they are conditions that are present in the space and so in the formation of meteorites.
Learn more about Earth's early atmosphere here: brainly.com/question/18289168
Answer:
Although direct calorimetry is considered to be the most precise technique for the measurement of metabolic rate, construction of such a chamber that is large enough for doing exercise physiology research (or any research for that matter) is extremely expensive and not at all mobile.
Explanation:
Direct calorimetry measures the heat production of an individual, in calories, when placed in an insulated chamber where the heat is transferred to surrounding water. This is a very accurate method of measuring energy expenditure.
Answer:
plants release water vapor
unlike asphalt, soil is not black.
The paler color reflects more light.
Explanation:
