Explanation

 Tetraethyl lead (TEL) was historically added to gasoline to increase its octane rating and reduce knocking, but due to its environmental concerns, it has largely been phased out. 

Explanation

The molecule that cannot form hydrogen bonding among themselves is All of the above. 

Hydrogen bonding occurs when a hydrogen atom is bonded to a highly electronegative atom (oxygen, nitrogen, or fluorine) in one molecule and is attracted to the lone pair of electrons on another electronegative atom in a different molecule. 

A) CH₂O (Formaldehyde):

While the oxygen is electronegative, the hydrogen is not directly bonded to it, so it cannot participate in hydrogen bonding.

B) CH₃CHO (Acetaldehyde):

Similar to A, the hydrogen is not directly bonded to the oxygen.

C) (CH₃ – CH₂)₃N (Trimethylamine):

Although the nitrogen is electronegative, the hydrogen atoms are not directly bonded to the nitrogen.

Explanation

According to Einstein, increasing the brightness of a beam of light without changing its color will increase the number of photons. 

Einstein's theory of light posits that light consists of discrete particles called photons.

Brightness is related to the number of photons present in a given area over a specific time.

When you increase the brightness of a light beam, you are essentially adding more photons to that beam,

While keeping the energy of each photon the same (which is related to its frequency and color).

Explanation

The first organic compound prepared in the laboratory was Urea. 

German chemist Friedrich Wöhler synthesized urea from ammonium cyanate in 1828,

Marking a significant milestone in organic chemistry. 

Explanation

Octyl acetate is a natural ester known for its fruity, orange-like aroma.

It is commonly used in flavorings and perfumes to mimic orange scent.

Explanation

The mass of one mole of electrons is 0.55g.      

- Mass of one electron ≈ 9.109 × 10⁻³¹ kg

- 1 mole of electrons = 6.022 × 10²³ electrons

- So, mass of 1 mole of electrons ≈  

  9.109 × 10⁻³¹ kg × 6.022 × 10²³ ≈ 5.48 × 10⁻⁴ kg ≈ 0.548 g

So the correct value is about 0.55 g

Explanation

The elements in group VIIA of the periodic table are called halogens.

This group consists of the following elements:

• Fluorine (F)
• Chlorine (Cl)
• Bromine (Br)
• Iodine (I)
• Astatine (At)
• Tennessine (Ts)

Explanation

The most stable hydrocarbon among the given options is trans-2-butene. 

Stability in alkenes:

• The stability of alkenes is primarily determined by the degree of substitution at the double bond.
• More substituted alkenes are generally more stable. 

Trans vs. Cis Isomers:

• In the case of 2-butene, the trans isomer is more stable than the cis isomer.
• This is because in the trans configuration, the alkyl groups on either side of the double bond are oriented away from each other, minimizing steric hindrance.
• In the cis configuration, the alkyl groups are on the same side, leading to steric repulsion and less stability. 

Explanation

Ethylene glycol (HOCH2CH2OH) is a 1,2-diol, and both periodic acid (HIO4) and lead tetraacetate (Pb(OAc)4)

They are strong oxidizing agents capable of cleaving the carbon-carbon bond between the adjacent hydroxyl groups in a glycol

Resulting in the formation of carboxylic acids. In the case of ethylene glycol, this would yield oxalic acid (HOOC-COOH). 

Explanation

Affinity for oxygen refers to how readily an element or compound combines with oxygen.

Magnesium (Mg) is a highly reactive alkaline earth metal that readily loses its two electrons to form a positive Mg2+ ion.

This ion then readily combines with oxygen to form magnesium oxide (MgO), demonstrating a strong affinity for oxygen.