Question

(a) What are Silicones? State the uses of Silicones.
(b) What are Boranes? Give a chemical equation for the preparation of Diborane.

Answer 1

Boranes' chemistry has resulted in advancements in synthetic methods, as well as structure and bonding. To begin, new synthetic techniques were needed to handle diborane and its many pyrophoric and volatile derivatives. A silicone, also known as polysiloxane, is a siloxane-based polymer. Colorless oils or rubber-like substances are the most common.

Complete answer:
(a) Silicones, also known as polysiloxanes, are a type of polymer. Any inert, synthetic compound made up of iterative units of siloxane is included in this category of polymers. It is an alternating chain of oxygen and silicon atoms that's frequently combined with hydrogen and carbon.
Silicones are the most common type of synthetic object today, and they are used in thousands of applications that provide safety and well-being in daily life.
Uses of Silicones:
Silicones come in a variety of forms, from liquids to solids, allowing engineers, inventors, and businesses to use them in a variety of industrial applications. Silicones, whether as rubbers, fluids, resins, silicone gels, or silicon glue, are essential ingredients in products that improve our lives because of their versatility. Silicones are used in a wide range of products, including computers, engineered spacecraft, shampoo, and baking moulds. Silicones can also be used in renewable energy systems, such as wind turbines and solar panels.

(b) Boron hydrides are referred to as borane in general. At room temperature, these boranes are gaseous substances. ${B_n}{H_{n + 4}}$ and ${B_n}{H_{n + 6}}$ are the general formulae for the two important boranes series.
Diborane Preparation:
Diborane was created by the reaction of a metal hydride with boron. In the industrial production of diborane, this method is widely used.
In small amounts, the reaction of iodine with sodium borohydride in diglyme can produce diborane.
$2NaB{H_4} + {I_2} \to {B_2}{H_6} + 2NaI + {H_2}$
A mixture of volatile boranes is formed when magnesium boride is heated with HCl.
$2M{g_3}{B_2} + 12HCl \to 6MgC{l_2} + {B_4}{H_{10}} + {H_2}$
${B_4}{H_{10}} + {H_2} \to 2{B_2}{H_6}$
At room temperature, pure diborane does not react with air or oxygen, but impure diborane produces ${B_2}{O_3}$ and a large amount of energy.
${B_2}{H_6} + 3{O_2} \to {B_2}{O_3} + 3{H_2}O$
$\Delta H = - 2165KJmo{l^{ - 1}}$
Trimethyl Borate is formed when diborane reacts with methyl alcohol.
${B_2}{H_6} + 6C{H_3}OH \to 2B{(OCH)_3} + 6{H_2}$
Ionic hydride reactivity:
When metal hydrides are used to treat it, it produces metal borohydrides.
Ammonia-based reaction:
When excess ammonia is used at low temperatures, diborane is produced. When heated to higher temperatures, it produces borazole.
Hydroboration:
At room temperature, the ether solvent Diborane adds alkenes and alkynes. Hydroboration is a reaction that is commonly used in synthetic organic chemistry, particularly for the addition of anti-Markovnikov.
${B_2}{H_6} + 6RCH = CHR \to 2B{(RCH - C{H_2}R)_3}$

Note:
Diborane is a chemical compound with numerous applications in various fields. It is used as a propellant in rockets. It is used to make borophosphosilicate glass, which is a type of glass. It is used as a reducing agent in the majority of chemical reactions.