1
AP EAPCET 2025 - 23rd May Morning Shift
MCQ (Single Correct Answer)
+1
-0

The radius of fourth orbit in $\mathrm{He}^{+}$ion is ' $R_1{ }^{\prime} \mathrm{pm}$ and radius of third orbit in $\mathrm{Li}^{2+}$ ion is ' $R_2{ }^{\prime} \mathrm{pm}$. The value of ( $R_1-R_2$ ) in pm is

A

132.25

B

529.00

C

264.50

D

793.50

2
AP EAPCET 2025 - 23rd May Morning Shift
MCQ (Single Correct Answer)
+1
-0

The de-Broglie wavelengths of two fast moving particles $X, Y$ are $1 \mathrm{~nm}, 3 \mathrm{~nm}$ respectively. Mass of $X$ is nine times the mass of $Y$. The ratio of kinetic energies of $X, Y$ is

A

$1: 3$

B

$1: 1$

C

$9: 1$

D

$1: 9$

3
AP EAPCET 2025 - 23rd May Morning Shift
MCQ (Single Correct Answer)
+1
-0

Electronic configurations of four elements $A, B, C, D$ are given below

(A) $1 s^2 2 s^2 2 p^6 3 s^1$

(B) $1 s^2 2 s^2 2 p^6 3 s^2 3 p^1$

(C) $1 s^2 2 s^2 2 p^6 3 s^2$

(D) $1 s^2 2 s^2 2 p^6 3 s^2 3 p^2$

The correct order of first ionisation enthalpy of these elements is

A

D $>$ B $>$ C $>$ A

B

C $>$ D $>$ B $>$ A

C

C $>$ A $>$ B $>$ D

D

D $>$ C $>$ B $>$ A

4
AP EAPCET 2025 - 23rd May Morning Shift
MCQ (Single Correct Answer)
+1
-0

A molecules has T -shape. The total number of electron pairs in the valence shell of central atom of it is

A

4

B

5

C

6

D

3