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44. Option (i) and (ii) 

Explanation: Depressants are materials that are added for the separation of ores that prevent certain types of particles from coming to froth and forming bubbles. For example, an ore containing ZnS and PbS, NaCN is used as a depressant.

When sulfur ores are blown in hot air along with silica, the solidified metal which is obtained has a blistered appearance due to SO₂ evolution.

The equation of the curve is $y=x^2+2\Rightarrow x^2=y-2$ - (1) and

lines are

$y=x$ - (2)

$x=0$ - (3)

$x=3$ - (4)

Equation (1)is a parabola with vertex (0,2)

Equation (2)is a straight line passing origin with shape = $tan\theta =1=\theta =45^{?}$

$\therefore$ The required area enclosed OBCDO = area (ODCAO)-area (OBAO)

Students willing to get a BE seat at UCEOU must follow the below-mentioned steps:

1. Ensure that eligibility requirements are met.

2. If eligible, apply for the preferred BE course on the institute's official website.

3. Appear for the TS EAMCET exam.

4. After the announcement of the results, participate in the TS EAMCET counselling process.

5. When allocated a seat, pay the admission fee to secure the seat.

24. As an effect of lanthanide contraction, the second and third rows of transition elements resemble each other. For example, zirconium and hafnium have similar radius i.e. 160pm and 159pm respectively. Due to this similarity in their size, they show similar physical and chemical properties. 

Lanthanoid contraction: Because the elements in Row 3 have 4f electrons. These electrons do not shield good, causing a greater nuclear charge. This greater nuclear charge has a greater pull on the electrons and result in the decrease in their size and atomic radii.

Yes, Google is one of the top recruiters of Saint Louis University graduates, however, it not the only major tech giant hiring students from SLU.

The likes of Deloitte & Facebook (Meta), are also known to recruit students from Saint Louis University.

Ernst & Young, Atheltico Ltd, NASA & Bayer are some other top recruiters at SLU.  

43. Option (i) and (ii)

In the vapor phase refining method, the metal is converted into its volatile compound and then is collected elsewhere. This involves two techniques:

1. Mond Process for refining Nickel: in this process, a volatile complex, nickel tetracarbonyl is formed when nickel is heated with a stream of carbon monoxide.

2. Van Arkel Method for refining Zirconium or Titanium: this method is basically used for removal of oxygen and nitrogen present as impurities in the Zr or Ti metal. These are heated in an evacuated metal with iodine. As iodine is more covalent than these metals, it volatilizes.

The equation of the given circle is

$=x^2+y^2=1$ - (1)

$=\; (x-1)2^{}+y^2=1$ - (1) - (2)

Equation (1) is a circle with centre 0 (0,0) and radius 1. Equation (2) is a circle with centre c (1,0) and radius 1.

Solving (1) and (2)

23. KMnO₄ act as an oxidising agent however it’s activity as oxidising agent is influenced by the pH of the solution i.e. acidic, basic or neutral solution. 

K₂Cr₂O₇ + 2KOH → 2K₂CrO₄ + H₂O

(Orange)                      (yellow)

 2K₂CrO₄ + H₂SO₄ → K₂Cr₂O₇ + K₂SO₄ + H₂O

(yellow)                                       (orange) 

VSIOET course admission is completely entrance-based. Students seeking to apply for any of the courses offered at the college must fulfil the admission criteria of the desired programme before applying for it. The courses are offered in various specialsiations such as Artificial Intelligence & Machine Learning, Computer Science Engineering, Electrical Engineering, Electronics & Communication Engineering, Management and Information Technology.

22. This is due to the inter conversion of dichromate (orange) to chromate ion (yellow). 

Cr₂O₇^2-   CrO₄^2-  

(orange)     (yellow) 

42. Option (i) and (iv)

(i) Carbon monoxide is the primary reducing agent in the furnace.

(ii) This is an endothermic reaction in which heat is absorbed from the furnace. As a result, it is critical not to add too much limestone, as this will cool the furnace. Calcium oxide is a basic oxide that reacts with acidic oxides in the rock, such as silicon dioxide. Calcium silicate is formed when calcium oxide reacts with silicon dioxide.

The equation given circle is

$\begin{array}{l}4x^2+4y^2=9\\ \Rightarrow x^2+y^2=\frac{9}{4}\\ \Rightarrow x^2+y^2={\left(\frac{3}{2}\right)}^2\end{array}$

i.e, centre (0,0), radius $r=\frac{3}{2}$

since $x^2=4y$ intersect the circle

we can put $x^2=4y$ in $x^2+y^2={\left(\frac{3}{2}\right)}^2$

$\begin{array}{l}\left(4y\right)+y^2=\frac{9}{4}\\ \Rightarrow y^2+4y-\frac{9}{4}=0\\ \Rightarrow 4y^2+16y-9=0\\ \Rightarrow 4y^2+18y-2y-9=0\end{array}$

$\begin{array}{l}\Rightarrow 2y\left(2y+9\right)-1\left(2y+9\right)=0\\ \Rightarrow \left(2y+9\right)\left(2y-1\right)=0\\ \Rightarrow y=\frac{-9}{2}\&y=\frac{1}{2}\\ \end{array}$

$y=\frac{-9}{2},x^2=4\times \left(\frac{-9}{2}\right)=-18$ which is not possible or $x^2$ cannot be (-)ve

21. 2MnO₄^-  +  16H⁺ +  5C₂O₄^2-  → 2Mn₂ +  +  8H₂O  +  10CO₂

KMnO₄ oxidises the oxalic acid to CO₂ and reduces itself to Mn²⁺  state. Mn²⁺ is colourless that’s why it seems that KMnO₄ has been disappeared. 

As $y=3$ intersect $y^2=4x$ at Athen,

$\begin{array}{l}{3}^2=4x\\ \Rightarrow x=\frac{9}{4}\end{array}$

$\therefore$ A has coordinate $\left(\frac{a}{4},3\right)$

Hence, area of curve = ${\displaystyle \underset{y=0}{\overset{y=3}{\int }}x}dy$

$\begin{array}{l}={\displaystyle \underset{0}{\overset{3}{\int }}\frac{y^2}{4}dy={\left[\frac{y3}{4\times 3}\right]}_0^3}\\ =\frac{3^3}{12}-\frac{0}{12}\\ =\frac{27}{12}=\frac{9}{4}uni{t}^2\end{array}$

$\therefore$ Option (B) is correct

41. Option (i) and (iii)

Explanation: Haematite is an ore of iron that can be calcined and reduced by carbon. In the metallurgical process, calamine ore is calcined ore that can be reduced by carbon. Hence, option (i) and (ii) are correct.

At UCEOU, students are offered eight specialisations under the BE programme for students to choose from. Under each specialisation, the institute offers 60 seats. However, under the BE in Biomedical Engineering course, the institute offers only 30 seats. To get a seat, students must appear for the TS EAMCET exam and appear for the subsequent counselling process.

Given equation of the circle is

∴ option (A) is correct