Answer:
Buckminsterfullerence is called an allotrope of carbon because it was discovered during an experiment involving a cluster of beam which uses laser to vapourise a graphite rod in a helium atmosphere to produce carbon plasmas.a mass sectrometry evidence from the experiment showed that carbon molecules with C60 were forming with a spheroidal geometry.so therefore it was included as an allotrope of carbon.
Answer:
To be enantiomers, a molecule must have at least three different atoms or groups connected to a central carbon.
Explanation:
To be structural isomers, the molecules must have the same formula and different structure, it means, the same number of each element. CH3CH2COOH and C3H6O2 have 3C, 6H, and 2O, so they can be structural isomers.
Cis-trans isomers occur in molecules with a double bond between carbons, and each carbon has to have 2 different atoms or groups connected to it.
Enantiomers are optic isomers, and to occur, the molecule has to have a chiral carbon (an asymmetric carbon), which is a central carbon connected to four different atoms or groups. So the third affirmative is false because it says that is necessary only three different atoms or groups connected to a central carbon.
Answer:
A) Dilute the unknown so that it will have an absorbance within the standard curve. Once the diluted unknown concentration is determined, the full strength concentration can be calculated if the dilution process is recorded. Beer's law only applies to dilute solutions, so diluting the unknown is better than making new standards.
Explanation:
Beer's law states that <em>absorbance is proportional to the concentrations of the absorbing species</em>. This is verified in the case of diluted solutions (0≤0.01 M) of most substances. <u>As a solution gets more concentrated, solute molecules interact between themselves because of their proximity. </u>When a molecule interacts with another, the change in their electric properties (including absorbance) is probable. That's why <u>the plot of absorbance versus concentration stops being a straight line</u>, and <u>Beer's law is no longer valid.</u>
Therefore, if the absorbance value is higher than the highest standard, dilutions should be made. Once this concentration is determined, the full strength concentration can be calculated with the inverse of the dilution.
Answer:
Some human activities that cause damage (either directly or indirectly) to the environment on a global scale include population growth, overconsumption, overexploitation, pollution, and deforestation, to name but a few.
Explanation:
Hope this helped!!!