CAT Questions

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A callous person is insensitive or emotionally hardened.

Hence, Callous is the opposite of Sympathetic, kind hearted, sensitive, nice,...

A redox reaction is a type of reaction which involves transfer of electrons among two species. This reaction is also called oxidation-reduction reaction.

In oxidation process, there is an increase in oxidation state of an atom, ion or molecule by losing the electrons.

In reduction process, there is a decrease in oxidation state of an atom, ion or molecule by accepting the electrons.

1)

In this reaction, Ba undergoes oxidation and Cl undergoes reduction.
This reaction is redox reaction.
In this reaction, oxidation number of Ba increases from 0 to +2 . So, Ba undergoes oxidation. The oxidation number of Cl decreases from 0 to -1. So, Cl undergoes reduction.

2) 

From this above reaction, it is clear that Aluminum undergoes oxidation and silver undergoes reduction.
Due to this, this reaction is redox reaction.

In this reaction, oxidation number of Aluminum increases from 0 to +1. So, aluminum undergoes oxidation. The oxidation number of silver decreases from +1 to 0. So, silver undergoes reduction.

3)

In this reaction, Mg undergoes oxidation and Br undergoes reduction.
This reaction is redox reaction.
The reactions 1, 3 and 4 are redox reactions.
In this reaction, oxidation number of Mg increases from 0 to +2 . So, Mg undergoes oxidation. The oxidation number of Br decreases from 0 to -1 . So, Br undergoes reduction.

Hence all the above reactions are redox reactions.

As water is cooled from 4 deg C to 0 deg C, the water reaches its freezing point and starts forming ice crystals. Then the volume of that ice cubes increases and its density decreases. Hence, it is the reason that ice will float on water as ice has less density than the water.

A change to the Constitution is called as An Amendment.

An Amendment ::

An Amendment is ratified after two-thirds of the House and Senate approve of the proposal and send it to the states for a vote. That Convention can propose as many amendments as it deems necessary. Then, three-fourths of the states must affirm the proposed Amendment.

Phencyclidine (PCP) is a drug used for its mind-altering effects. It is also known as Angel dust. As a recreational drug, it is typically smoked, but may be taken by mouth, snorted, or injected. It may also be mixed with cannabis or tobacco.

Causes and Effects ::

* PCP may cause hallucinations, distorted perceptions of sounds, and violent behavior.

* Its effects include seizures, coma, addiction, and an increased risk of suicide.