A strong acid- strong base titration is performed using a phenolphthalein indicator. Phenolphtalein is chosen because it changes color in a pH range between 8.3 – 10.
D . on orbits or energy levels around the nucleus
Explanation:
A chemical reaction is defined as the reaction which leads to change in chemical composition of the reactants due to which there occurs formation of a new compound.
For example, when Ethan heats a substance and observes that the substance turns from a brown solid to a black powder then it means heating has lead to a chemical change in the brown solid because of which it has turned into a black powder.
Whereas if there occurs no change in chemical composition of the reactants then we can say that a physical change has occurred.
For example, change in shape, size, mass etc of a substance are all physical changes.
Hence, we can conclude that Ethan best defend his conclusion as a chemical change.
1) C because potential energy is always at the top first and has to most energy to speed down more.
2)A because potential energy is always at the top first
3)B because kinetic energy is when it starts to drop; so the perfect word for that is moving.
Physics<span> beyond the Standard </span>Model<span> (BSM) refers to the theoretical developments needed to ... Yet, the Standard </span>Model<span> does not supply any fundamental </span>particles<span> that are good dark matter candidates. .... compared to their mass—while formation of structures </span>similar<span> to the galaxies in our </span>universe<span>requires cold dark matter.</span>