Bihar PGT Chemistry Mock Test - 2 - Bihar PGT/TGT/PRT MCQ

The sentence is grammatically correct.
Hence, there is no error in the given sentence.

The correct word is 'who' which is a pronoun used to introduce a clause giving further information about a person or people previously mentioned.

The correct answer is Option 2, i.e., ‘spare’.
The word ‘castigate’ means ‘to subject to severe punishment.’ The word ‘spare’ has an opposite meaning of ‘to choose not to punish.’ Hence, the correct option is Option 2.

The sentence indicates the contraction of skeletal muscles. Rhythmic contraction would mean a strong, regular pattern of movement or sound, while nonmetrical, arrhythmic, and unrhythmic mean the opposite.
In the above sentence, Rhythmic contraction suits the meaning of the sentence. Thus, option 4 is the correct answer.

परिवर्तन शुद्ध वर्तनी है।

शेष विकल्प असंगत है।

परिवर्तन- बदलाव, हेरफेर, तबदीली, फेरबदल इत्यादि इसके पर्यायवाची है।

निर्भय शब्द में निर् उपसर्ग है। निर् का अर्थ है। बाहर तथा भय का अर्थ है। डर जबकि निर्भय का अर्थ है  निडर।

निर्भय = निर् + भय 

उपसर्ग ऐसे शब्द होते है जो शब्दों के आगे लगकर शब्दों का अर्थ बदल देते है उपसर्ग कहलाते है।

उपसर्ग शब्द + अन्य शब्द = परिवर्तित शब्द 

दुबला-पतला - लड़का युग्म में लिंग की शुद्धता है।

अन्य शुद्ध युग्म:-

टोपी - काली 

सुनहरा - पत्ता

उड़ती हुई - चिड़िया

The figure is given below:-

Sunny faces east direction then move 45° clockwise direction and the move 135° anticlockwise direction. Now Sunny faces north direction.

Hence, "option 2" is the correct answer.

Explanation:

• Evolutionary biology: It is a field of science that deals with the study of evolutionary processes like natural selection, speciation & common descent that has led to the diversification of life on earth.
• Charles Darwin is known as the father of ''Evolutionary Biology''.
• Darwin proposed a theory of evolution called natural selection in the year 1859. According to it those populations which are a better fit (reproductively fit) in an environment will be selected by nature and will survive more.
• Charles Darwin wrote a book named ''The origin of species'' which is considered to be the foundation of evolutionary biology.

Additional Information 

• Herbert Spencer- He Was best known for the introduction and application of evolutionary theory to philosophy, psychology, and social sciences
• The famous phrase 'Survival of the fittest' to mean Natural Selection was coined by Herbert Spencer. He originated this phrase after the publication of famous biologist Charles Darwin’s book ‘Origin of Species’ which talked about ‘Natural Selection’.
• Julian Huxley was an English biologist, philosopher, educator, and author who greatly influenced the modern development of embryology, systematics, and studies of behaviour and evolution.
• Stanley Miller along with H.C. Urey provided experimental evidence of ''chemical evolution''

Concept:

• The laws dealing with ideal gases naturally called ideal gas laws, and the laws determined in the seventeenth century by Boyle's observational work and in the eighteenth century by Charles.
• The Boyles Law states that the gas pressure is inversely proportional to the gas volume for a given mass of gas stored at a constant temperature.
• Charles Law states that the gas volume is directly proportional to the gas temperature for a given fixed mass of gas stored at a constant pressure. 
• An ideal gas is a gas that follows the equation:

PV = nRT at all temperatures and pressure, where P = Pressure of the ideal gas. V = Volume of the ideal gas n = Amount of ideal gas measured in terms of moles 

R = Universal gas constant T = Temperature

Mole Concept -

•  The quantity one mole of a substance signifies 6.022 × 10²³ number of particles of that substance which may be atoms, molecules, or ions.
• The quantity is a universal constant like Dozen, Gross, etc., and is known as Avogadro number, denoted by NA. after the scientist Amedeo Avogadro.
• Examples- In one mole of H₂, there are 6.022 × 10²³ molecules of hydrogen, and the number of atoms is 2 × 6.022 × 10²³, as one molecule of hydrogen contains two-atom each.
• The mass of one mole of a substance is called its Molar Mass (M) or Atomic mass expressed in grams.
• The volume occupied by a mole of gas is 22.4 L at NTP, called its Molar Volume.
• The no. of moles (n) is calculated as =

The number of particles / Avogadro’s number.

To summarise, we can say, 

Calculation:

• The molar mass of 1 mole of H₂SO₄ is =

2 × 1 + 32 + 4 × 16 = 98g

• The molar mass of 1 mole of Silver, Ag is its molecular mass 108g.
• The molar mass of CO₂ is = 12 + 2× 16 = 44g.
• 44g of CO₂ means one mole.
• 1 mole of Oxygen weighs 16 + 16 = 32g.
• Hence, the highest mass is of 1 mole of Ag.

The correct answer is Pataliputra.

Key Points

• Pataliputra was the capital of the Mauryan Empire.
• The empire lasted from 321 to 185 BCE.
• The Mauryan Empire was founded by Chandragupta Maurya and the most popular ruler of the empire was Ashoka.
• Mauryan dynasty had three important rulers:
  • Chandragupta
  • Bindusara
  • Ashoka

 Thus, we can say that Pataliputra was the capital of the Mauryan Empire.

Additional Information

• The most important cities of the empire were the capital Pataliputa, Ujjain and Taxila.

Option 1 is correct, i.e. Nagaland.

Key Points

• The Ao tribe of Nagaland has one such special festival, known as the Moatsu festival. 
• This festival is celebrated after seeds have been sown in the fields.
• Men and women of the tribe gather around large outdoor fires and performing traditional dances.

Additional Information

Some important festivals of Northeastern states are:

The word that can be suffixed to form new words is ‘ure’

Fail + ure = Failure

Press + ure = Pressure

Depart + ure = Departure

Advent + ure = Adventure

The correct answer is option 4.

Key Points

Article 75 of the Indian Constitution mentions that a Prime Minister is one who is appointed by the President.

• There is no specific procedure for his election or appointment.
• Article 74(1) states that there shall be a Council of Ministers with a Prime Minister at the head to aid and advise the President. 
• President of India appoints a person as the Prime Minister who is either the leader of the party which holds a majority of seats in the Lok Sabha or is a person who is able to win the confidence of the Lok Sabha by gaining the support of other political parties.

• All other ministers are appointed by the President on the advice of the Prime Minister.

Thus, it is clear that while appointing the Prime Minister, the President selects the leader of the alliance or party that has the support of the majority in Lok Sabha.

Additional Information

• President can also appoint Prime Minister at his own discretion but only when no party has a clear majority in the Lok Sabha. 

The description is as follows:

Hence, ‘COW’ is the odd one out.

The Logic followed here is:

The third number = The First number × (second number ÷ 2)

In Row 1:- 10, 4, 20

The third number = 10 × (4 ÷ 2)

= 10 × 2 = 20

In Row 2:- 15, 8, 60

The third number = 15 × (8 ÷ 2)

= 15 × 4 = 60

Similarly,

In Row 3:- 25, 8, ?

The third number = 25 × (8 ÷ 2)

? = 25 × 4 = 100

Hence, the correct answer is "100".

Additional Information 

The most common pattern asked in exams are based on:

• It could be the sum of two numbers divided by a constant
• It could be the average of numbers.
• It could be in the form of alphabets, where alphabets are increased by constant or increased by the square of numbers or increased by prime numbers.
• It could be the difference of product of two diametrically opposite numbers.
• It could be the difference in the sum of adjacent numbers.
• The difference of the numbers could be in the pattern 13 ± 1, 23 ± 1,  and so on.
• The difference of the numbers could be in the pattern 12 ± 1, 22 ± 1, and so on.
• Numbers could be 12, 22, 32, and so on or 13, 23, 33, and so on.
• The difference could be prime numbers or the difference could be the square of prime numbers.
• The difference could be in the form of N2 ± N or N3 ± N.
• The difference could be in the form of ×N + N or ×2 + 1, ×2 + 2, ×2 + 3, and so on.
• The difference could be in the form of ×2 ± 1 alternatively.
• Numbers could be ×1, ×2, ×3, and so on. 

The correct answer is Option B.
 
Molal elevation constant is a characteristic constant for a given solvent. It is the elevation of boiling point produced when one mole of solute is dissolved in 1 kg of solvent. The proportionality constant, Kb, is called the molal boiling point elevation constant. It is a constant that is equal to the change in the boiling point for a 1-molal solution of a nonvolatile molecular solute.

The time taken for half the reaction to complete, i.e., the time in which the concentration of a reactant is reduced to half of its original value is called half-life period of the reaction. But it is impossible to perform 100% of the reaction. Whole of the substance never reacts because in every half-life, 50% of the substance reacts. Hence, time taken for 100% completion of a reaction is infinite. 

∆S= 2.303nR × log(V₂/V₁)Here n=2, R=8.314, V2= 10, V₁= 1

½ H₂(g) + ½ Cl₂(g) → HCl(g) ∆_fH° = -22.10 kcal mol^-1  -----(I)
HCl(g) + H₂O(l) → H⁺(aq) + Cl^-(aq)     ∆_solutionH° = -17.9 kcal mol^-1 -----(II)
Let us add (I) and (II), we get
½ H₂(g) + ½ Cl₂(g) → H⁺(aq) + Cl-(aq) ∆_rH° = -40.0 kcal mol^-1
∆_rH° = ∑∆H_product  -  ∑∆H_reactant = ∆_fH_Cl- (since enthalpy of formation of H, H₂ and Cl₂ are 0)
∆_fH_Cl- = -40.0

The correct answer is option D
For Na₂​SO₄ ​: −i = n
Na₂​SO₄ ​⟶ 2Na⁺ + SO₄²⁻​​
                         n=2
i=1−α+nα
i=1−α+2α
i=1+2α

Explanation of Chelating Ligand
A chelating ligand is a molecule that forms multiple bonds with a single metal ion. In other words, it can bind to a metal ion at more than one point, creating a ring-like structure. This process is known as chelation. Chelating ligands have two or more donor atoms, which allow them to form multiple bonds with a single metal ion. These ligands are used in various fields such as medicine, chemistry, and environmental science due to their ability to sequester metal ions.

Examination of Options
A: Cl^- Chloride ion (Cl-) is a monodentate ligand, meaning it can bind to a metal ion at only one point. Therefore, it is not a chelating ligand.
B: DMG DMG, or Dimethylglyoxime, is a type of ligand that can bind to a metal ion at two points, forming a five-membered ring. Thus, DMG is a chelating ligand.

C: H₂O Water (H₂O) is a monodentate ligand, meaning it can bind to a metal ion at only one point. Therefore, it is not a chelating ligand.
D: OH^- Hydroxide ion (OH^-) is a monodentate ligand, meaning it can bind to a metal ion at only one point. Therefore, it is not a chelating ligand.

Conclusion
Therefore, out of the given options, only DMG (Dimethylglyoxime) is a chelating ligand. Hence, the correct answer is B: DMG.

According to option A chiral compound at least have one chiral carbon but compounds other than carbon and also chiral like NCl Br I is chiral. According to option b a compound containing only one ka kalakaron is always is always correct that is statement is true it is the minimum requirement for a carbon atom to become chiral. Efficiency is not necessary to be true all the time compound will not be superimposable on its Mirror image. And for option d a plane of symmetry is sufficient but not a mandatory to give achiral compound.

Option b: Decrease concentration of sample four times and measure the optical rotation. Explanation:

• Optical rotation is directly proportional to concentration (specific rotation = observed rotation/concentration).
• If you decrease the concentration of the chiral compound in the sample, the observed optical rotation will decrease proportionally.
• If the initial observed rotation is indeed +60° and not -300°, decreasing the concentration will still result in a positive rotation, but it will be lower.

The other options are less likely to provide useful information in this context.

• Phenol is C₆​H5​(OH) while benzyl alcohol is C₆H₅​(CH₂​OH). 
• Here there is a difference of −HC2​ between their molecular formula.
• According to the definition of homologous series, the adjacent members of the series differ by −CH₂​ group.
• Thus Phenol and benzyl alcohol are homologous of each other.

Sulphur exists in elemental form which is extracted by Frasch process.
Sulphide ores are zinc blende (ZnS), galena (PbS), copper pyrites (CuFeS₂), cinnabar (HgS),
Sulphate ores are gypsum (CaSO₄. 2H₂O), epsom (MgSO₄ .7 H₂O) .

Be²⁺ →  Al³⁺ + Be²⁺ is diagonaly similar with Al³⁺ & Al³⁺ is amphoteric in nature.

The electronic configuration of Be is 1s²2s². We can see that there are only 4 orbitals in its valence shell( they are s and p). In other words, d orbital is absent. So, Be shows ccoordination no 4 and not 6 as like other members of its group.

The rows of the periodic table are called periods, while the columns of the table are called groups.

The bond pair of electrons is shared by two atoms whereas the lone pair of electrons is only under the influence of central atom.

So the electron cloud of lone pair occupies more space as compared to the bond pair.

This causes greater repulsion between the lone pairs as compared to lone pair-bond pair and bond pair-bond pair interactions.