Answer:
What material structure explanation lies behind the fact that the propagation velocity of longitudinal waves is the lowest in gases and the highest in solids?
a substance dissolves.
like adding a soluble salt to water, it just dissolves, i.e dissociates homogeneously as water is able to dissociate salts (ionic compounds) into its ions. (it can also dissociate other non-ionic compounds like HCL)
the salt still remains chemically as a salt and is unchanged chemically thus it is not an indication of a chemical reaction as no chemical reaction has taken place.
the formation of a precipitate is a chemical reaction because a new substance (i.e new chemical) is formed. For example adding aqueous sodium hydroxide into an aqueous solution with CU2+ cations will form a blue precipitate (that is copper (II) hydroxide which is insoluble, hence it precipitates). Since a new chemical is formed, a chemical reaction has taken place and thus indicates a chemical reaction.
color change... im not sure but usually a color change will only occur when a new substance is formed. Like iron corrodes (i.e rust) slowly in moist air to form hydrated iron (III) oxide that is rust. (brown color).
usually adding a mixture to a mixture has little energy change, i.e little heat taken in by the reaction mixture or little heat given out by the reaction mixture. Whereas when a new substance is formed, there is usually noticeable energy change like the container gets colder or hotter (without heat being supplied of course). For example dissolving basic oxides into water releases energy ( more energy released than gained = exothermic reaction).
i think that should be the answer... hope it helped :D
Answer:
Southern state and local elections in 1876 differed from those in previous years in that the election of 1876 was one of the closest races in American history. It tested the Constitution and resulted in a compromise that ended Reconstruction in America.
The election of 1876 between Rutherford B. Hayes and Democrat Samuel Tilden of New York was one of the most hostile, controversial campaigns in American history. The vote was 8-7 along party lines to award the disputed electoral college votes to Hayes, making him the winner.
Explanation:
The Compromise of 1876 is known for being the catalyst for the end of Reconstruction era, it was one of the most contentious and controversial presidential elections in American history.
Republican nominee Rutherford B. Hayes faced Democrat Samuel J. Tilden. After a controversial post-election process, He lost the popular vote to Democrat Samuel J. Tilden but he won an intensely disputed electoral college vote after a Congressional commission awarded him twenty contested electoral votes Hayes was declared the winner. The Hayes-Tilden Compromise is often seen as the final point that brought an end to Reconstruction, as it led to the removal of the US army from the South.
As Florida's Supreme Court had earlier declared a Democratic victory in the 1876 gubernatorial election, Democrats had been restored to power all across the South. The Compromise of 1876 effectively ended the Reconstruction era.
Southern Democrats' promised to protect civil and political rights of blacks as they were not kept, and to end of federal interference in southern affairs. This led to widespread disenfranchisement of blacks voters. Other factors that contributed to the end of Reconstruction were the Panic of 1873 and political corruption in the United States.
The Compromise of 1877 (the Great Betrayal) was an informal, unwritten deal, that settled the intensely disputed 1876 U.S. presidential election. It resulted in the United States federal government pulling the last troops out of the South, and formally ended the Reconstruction Era.
Your weight #sorryfortheweight
A bees wings move so rapidly that studying them, even seeing them, has proved difficult.
The honeybees have a rapid wing beat honeybee flaps its wings 230 times every second.
Therefore, a bee flaps its wings over 200 times in about 1ms
