Answer:
Explanation: Mendeleev arranged the elements on the basis of their atomic mass. Melting and boiling point were used as the physical characteristics in deciding the position of elements. He arranged the elements and wrote the formula of their oxides and hydrides which seemed to possess same chemical formula.
Explanation:
Answer:
The molar mass of the gas is 44 g/mol
Explanation:
It is possible to solve this problem using Graham's law that says: Rates of effusion are inversely dependent on the square of the mass of each gas. That is:

If rate of effusion of nitrogen is Xdistance / 48s and for the unknown gas is X distance / 60s and mass of nitrogen gas is 28g/mol (N₂):

6,61 = √M₂
44g/mol = M₂
<em>The molar mass of the gas is 44 g/mol</em>
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I hope it helps!
Answer:
The correct answer is thermophiles.
Explanation:
Thermus aquaticus are heat resistant bacteria because these bacteria can survive under adverse environmental conditions like high temperature.
These bacteria belong to one of the most heat-loving groups of extremophiles that are thermophiles. Thermophiles are present in volcanic soil, geysers and around deep-sea vents where the temperature is extremely high.
Thermus aquaticus bacteria is used to manufacture an enzyme called Taq DNA polymerase, which is heat resistant and also an important factor in molecular biology.