While most constellations are only visible to us in different seasons, some are always there 24/7/365 because they are positioned close to the Polar Axis, or the Polaris.
Answer: A. To change the potential energy of the reactants.
Explanation:
Catalysts make such a breaking and rebuilding happen more efficiently. They do this by lowering the activation energy for the chemical reaction. Activation energy is the amount of energy needed to allow the chemical reaction to occur. The catalyst just changes the path to the new chemical partnership.
Answer:
Option D is Correct answer
The correct answer is - A) The major constituents of air are gaseous elements.
With the statement ''the major constituents of air are gaseous elements'' we can easily conclude that the air is a mixture. The reason for that is that we have a plural usage of the word element, elements, which mean that there are multiple elements that make up the air.
The air is indeed predominantly a mixture of gaseous elements. The most abundant gas in the air being the nitrogen with 78.9%, oxygen with 20.95%, argon 0.93%, and carbon dioxide 0.04%, with lesser amounts of other gases also be present in it. The water vapor is also present in the air, though it is variable, being around 1% at sea level, but only 0.4% over the entire atmosphere.
