Explanation

Sodium chloride (NaCl) forms ionic bonds, which are considered the strongest type of bonding in solids.

These bonds involve a strong electrostatic attraction between positively charged sodium ions (Na+) and negatively charged chlorine ions (Cl-).

This results in a stable crystal lattice structure, requiring a significant amount of energy to overcome and melt the compound. 

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 formation of the primitive streak occurs during the gastrula stage of embryogenesis. 

The primitive streak is a crucial structure that appears at the beginning of gastrulation,

A stage where the three germ layers (ectoderm, mesoderm, and endoderm) are established.

It serves as a pathway for cells to migrate and differentiate into these germ layers

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

The kidneys are responsible for filtering blood and regulating the amount of water and electrolytes excreted in urine.

They can adjust the concentration of urine depending on the body's hydration needs.

This makes them the primary organ for controlling water balance. 

Explanation

 Gonadotropic hormones, like follicle-stimulating hormone (FSH) and luteinizing hormone (LH),

They are specifically secreted by specialized cells called gonadotrophs within the anterior pituitary gland. 

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

 If the temperature of the source of heat increases, the efficiency of a Carnot engine will increase.

The efficiency of a Carnot engine is directly related to the temperature difference between the hot and cold reservoirs.

A higher source temperature leads to a greater temperature difference and thus, a higher efficiency. 

Explanation

Sound waves diffract (bend) around corners, allowing us to hear them,

While light waves do not diffract as much, making it impossible to see around corners.

Diffraction is the bending of waves around obstacles or through openings.

Sound waves have longer wavelengths than light waves, which makes diffraction more noticeable for sound.

Polarization is a property of transverse waves, and while light waves can be polarized, sound waves cannot.

Dispersion is the separation of waves into different frequencies,

And while it can occur with light, it's not why we can hear around corners.