The “steady state theory” suggested that the universe has always existed and maintainsthe same structure. This theory was later discredited due to which discovery? (S6E1.a) Your

A. The amount of hydrogen in the universe is extremely high to remain steady.

B. The scale of the universe is much greater than was previously understood.

C. The shift of light toward longer wavelengths indicates that most galaxies are moving away from Earth.

D. More powerful telescopes have made observations of planets orbiting stars other than the Sun.

the solar system used to have much dust particles option no d

the correct answer is b. a strong acid completely dissociates to its ions when dissolved in water. completely dissociates to and ions. a is incorrect because does not fully ionize to and ions and some remain as the compound . c and d are incorrect because, and do not fall into the category of bronsted lowry acids. a bronsted lowry acid is a proton donor and since both molecules do not have a proton to donate they are not bronsted lowry acids. likewise,   if we use the lewis acid definition, they cannot be acids. a lewis acid is an electron pair acceptor. both and have a complete octet so can not accept any electrons which disqualifies them as acids.

chemical changes occur when a substance combines with another to form a new substance, called chemical synthesis or, alternatively, chemical decomposition into two or more different substances. these processes are called chemical reactions and, in general, are not reversible except by further chemical reactions. some reactions produce heat and are called exothermic reactions and others may require heat to enable the reaction to occur, which are called endothermic reactions. understanding chemical changes is a major part of the science of chemistry.