Explanation:
In liquids, the molecules are held by less strong intermolecular forces of attraction as compared to solids. Due to which they are able to slide past each other. Hence, they have medium kinetic energy.
In gases, the molecules are held by weak Vander waal forces. Hence, they have high kinetic energy due to which they move rapidly from one place to another leading to more number of collisions.
So, when at 298 K and 1 atm 
exists in liquid state and 
exists as a gas then it means there occurs strong force of attraction between the molecules of due to which it exists in liquid form.
Thus, we can conclude that at 298 K and 1 atm, bromine is a liquid with a high vapor pressure, whereas chlorine is a gas. This provides evidence that, under these conditions, the forces among 
molecules are greater than those among 
molecules.
Answer: The calcium and magnesium metal samples had undergone a chemical reaction (oxidation) with the oxygen present in the air around the shelf to form oxides which caused them to lose their metallic luster overtime. This process is known as tarnishing.
Aluminium also undergoes this process but at a slower rate due to its lower reactivity compared with calcium or magnesium.
Explanation:
Calcium and magnesium belong to the group 2 of the periodic table of metals,generally called alkaline earth metals. They are very reactive and on exposure to air, they react with the oxygen present in air to form <em>coatings/films</em> of calcium oxide and magnesium oxide respectively over the metals. This causes the metals to lose their metallic shine or luster overtime.
Aluminium also undergoes this process generally known as <em>tarnishing</em> forming aluminium oxide but at a slower rate when compared to calcium or magnesium due to their being more reactive than aluminium is.
Scientists believe that the solar system was formed when a cloud of gas and dust in space was disturbed, maybe by the explosion of a nearby star(called a supernova). This explosion made waves in space which squeezed the cloud of gas and dust.
Answer:
Letter A
whether a trait is learned or inherited
Explanation:
The nature versus nurture debate involves the extent to which particular aspects of behavior are a product of either inherited (i.e., genetic) or acquired (i.e., learned) influences. Nature is what we think of as pre-wiring and is influenced by genetic inheritance and other biological factors.
