Explanation

Astatine is considered the rarest naturally occurring element on Earth, making it the "rare halogen" among the group which includes fluorine, chlorine, bromine, and iodine. 

Explanation

When ethanol is in excess and the temperature is around 140°C, concentrated H₂SO₄ acts as a dehydrating agent and promotes the formation of diethyl ether:

2CH₃CH₂OH → CH₃CH₂–O–CH₂CH₃ + H₂O

So, the major product is ether (specifically diethyl ether) under these conditions.

Explanation

Whey, the liquid part of milk after curdling, contains lactose, proteins, and nutrients that can be used by both:

- Bacteria – for fermentation (e.g., in yogurt or cheese production)

- Yeast – as a nutrient source in certain fermentation processes

Explanation

Good food hygiene prevents food poisoning and food waste.
It also prevents allergic reactions.

Explanation

Newton's laws are not valid in a non-inertial frame. 

An inertial frame is a frame of reference where an object at rest remains at rest and an object in motion continues to move at a constant velocity unless acted upon by an external force.

Newton's laws are valid in inertial frames. 

A non-inertial frame is a frame that is accelerating with respect to an inertial frame.

In these frames, Newton's laws do not hold true because apparent forces seem to exist due to the acceleration of the frame

Explanation

Sticky ends are formed when a restriction enzyme cuts DNA at specific locations, leaving short, single-stranded overhangs with unpaired bases at the ends.

These unpaired bases can then form hydrogen bonds with complementary unpaired bases on another DNA fragment, allowing them to "stick" together, hence the name "sticky ends". 

Explanation

A gas being cooled is a system where entropy is decreasing. 

When a gas is cooled, its molecules slow down and become more ordered, leading to a decrease in entropy. 

Explanation

The basic principle of providing first aid is to give immediate care, stop the injury, and make it possible to hospitalize the victim.

Explanation

 In the small intestines, bile emulsifies fats while enzymes digest them.

The intestinal cells absorb the fats.

Explanation

Light travels faster in a vacuum than in any other medium.

The speed of light traveling through a vacuum is exactly 299,792,458 meters (983,571,056 feet) per second

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ND4-12-2022