1
WB JEE 2026
MCQ (Single Correct Answer)
+1
-0.25
Change Language

The mass of an electron is $9 \cdot 1 \times 10^{-31} \mathrm{~kg}$ .If its K .E.is $3 \cdot 0 \times 10^{-25} \mathrm{~J}$ ,its wavelength is(approximately)

A

250 nm

B

400 nm

C

990 nm

D

850 nm

2
WB JEE 2026
MCQ (Single Correct Answer)
+1
-0.25
Change Language

The calculated magnetic moment for low spin $[\operatorname{Ru}(E D T A)]^{-}$isWB JEE 2026 Chemistry - Coordination Compounds Question 1 English

A

2.73 BM

B

1.73 BM

C

3.23 BM

D

0.00 BM

3
WB JEE 2026
MCQ (Single Correct Answer)
+1
-0.25
Change Language

Glucose is added to 1 litre of water to such an extent that $\Delta T_f / K_f$ equals to $\frac{1}{1000}$ .The weight of glucose added is

A

180 gm

B

18 gm

C

1.8 gm

D

0.18 gm

4
WB JEE 2026
MCQ (Single Correct Answer)
+2
-0.5
Change Language

A $5.0 \mathrm{~cm}^3$ solution of $\mathrm{H}_2 \mathrm{O}_2$ liberates 1.27 g of iodine from an acidified KI solution. The percentage strength of $\mathrm{H}_2 \mathrm{O}_2$ is close to

A

$11 \cdot 2$

B

$5\cdot8$

C

$1\cdot9$

D

$3 \cdot 4$