<span>The answer is true that Group 1A elements (except for hydrogen) are the
alkali metals. Groups 2A are alkaline earth metals. Group 3B-12B are transition
metals. Group 3A to 4A except Boron, Carbon, Nitrogen, oxygen, silicon,
phosphorus, sulfur, germanium, astatine, selenium, antimony, tellurium, polonium
are basic metal. Carbon, nitrogen, oxygen, phosphorus, sulfur and selenium are
nonmetals. Boron, silicon, germanium, astatine, antimony, tellurium and polonium
are metalloids. Groups 7A are halogens. Groups 8A are noble gases. The lower
part of the periodic table are lanthanides and actinides.</span>
Answer:
blue
Explanation:
Red light has a longer wavelength, a smaller frequency, and thus a photon energy which is smaller than blue light
A and C are the correct answers. Because there is no gravity to pull fluids down, they are in your face and hands more than normal. Our bones and muscles become weaker because without gravity objects lack weight.
<h2>Entropy of the system decreases when methane gas and oxygen gas combust to form carbon dioxide and water.</h2>
Explanation:
- Salt crystals when dissolved in water the bond between the molecules of crystals are broken down increasing the movement between the atoms hence entropy is increased.
- When air escapes from a hole in the balloon,the entropy increases as the air present inside the balloon occupies small volume as compared to outside.
- Ice when melts at room temperature its entropy increases because the molecule in the ice are closely packed hence less movement between the molecules.
- When water boils the kinetic energy increases or themovement between the atoms increases which increases the entropy.
Hence, the option (a), (b), (c), and (d) are not suitable to the statement that "the entropy of the system decreases".
- During combustion of methane gas there is release of carbon dioxide gas and water .Here, entropy decreases due to the formation of water which is due to overall decrease in the kinetic energy of the system.
