Answer:
See explanation
Explanation:
Light is a form of energy. Both ultraviolet light and xrays are part of the electromagnetic spectrum.
As was said in the question, ultraviolet rays is absorbed by the rubber. We must know that prolonged exposure of this piece of rubber to incident ultraviolet light causes the vaporization of volatile materials in the rubber.
When volatile materials in the rubber vaporize, the rubber can become solid. Thus, ultraviolet light can cause rubber to become solid.
However, not all types of light can do this hence it does matter the type of light that falls on the rubber material.
SiO2 is the only possible choice because the other formulas contain metals. how do we know this? because the other formulas contain elements located on the left of the “staircase” on the periodic table that separates metals from non-metals.
Answer:
<span>In the addition of hbr to 1-butyne the electrophile in the first step of the mechanism is <u>Hydrogen atom of HBr</u>.
Explanation:
In this reaction first of all HBr approaches the triple bond. A Pi Complex (weak inter-molecular interactions) is formed between the two molecules. And the triple bond attacks the partial positive hydrogen atom creating a negative charge on Bromine along with positive charge on itself (Sigma Complex). In second step the negative Bromide attacks the positive carbon of Butyne.</span>
Autoionization Reactions are those reactions in which ions or molecules ionizes spontaneously without adding any external reagent.
For Example,
Autoionization of water.
H₂O + H₂O ⇆ H₃O⁺ + OH⁻
Autoionization reaction of Methanol is shown below,