1
AP EAPCET 2025 - 22nd May Evening Shift
MCQ (Single Correct Answer)
+1
-0

One mole of $\mathrm{C}_2 \mathrm{H}_5 \mathrm{OH}(l)$ was completely burnt in oxygen to form $\mathrm{CO}_2(g)$ and $\mathrm{H}_2 \mathrm{O}(l)$. The standard enthalpy of formation $\left(\Delta_f H^{\ominus}\right)$ of $\mathrm{C}_2 \mathrm{H}_5 \mathrm{OH}(l), \mathrm{CO}_2(g)$ and $\mathrm{H}_2 \mathrm{O}(l)$ is $x, y$, $z \mathrm{~kJ} \mathrm{~mol}^{-1}$ respectively. What is $\Delta_r H^{\ominus}\left(\right.$ in $\left.\mathrm{kJ} \mathrm{mol}^{-1}\right)$ for this reaction?

A

$(2 y+3 z+x)$

B

$(2 y-3 z+x)$

C

$(x-2 y-3 z)$

D

$(2 y+3 z-x)$

2
AP EAPCET 2025 - 22nd May Evening Shift
MCQ (Single Correct Answer)
+1
-0

At $25^{\circ} \mathrm{C}, K_a$ of formic acid is $1.8 \times 10^{-4}$. What is the $K_b$ of $\mathrm{HCOO}^{-}$?

A

$1.8 \times 10^{-10}$

B

$5.55 \times 10^{-4}$

C

$5.55 \times 10^{-11}$

D

$5.55 \times 10^{-12}$

3
AP EAPCET 2025 - 22nd May Evening Shift
MCQ (Single Correct Answer)
+1
-0

At $T(\mathrm{~K})$, the following gaseous equilibrium is established.

$$ W+X \rightleftharpoons Y+Z $$

The initial concentration of $W$ is two times to the initial concentration of $X$. The system is heated to $T(\mathrm{~K})$ to establish the equilibrium. At equilibrium the concentration of $Y$ is four times to the concentration of $X$. What is the value of $K_C$ ?

A

0.375

B

1.333

C

2.666

D

5.333

4
AP EAPCET 2025 - 22nd May Evening Shift
MCQ (Single Correct Answer)
+1
-0

4 mL of ' $X$ volume' $\mathrm{H}_2 \mathrm{O}_2$ on heating gives 80 mL of oxygen at STP. The value of $X$ is

A

10

B

20

C

15

D

40