JEE Main 2023 (Online) 15th April Morning Shift | s-Block Elements Question 1 | Chemistry

This chapter is currently out of syllabus

JEE Main 2023 (Online) 15th April Morning Shift

MCQ (Single Correct Answer)

-1

Out of Syllabus

Given below are two statements : One is labelled as Assertion A and the other is labelled as Reason R :

Assertion (A) : $\mathrm{BeCl}_{2}$ and $\mathrm{MgCl}_{2}$ produce characteristic flame

Reason (R) : The excitation energy is high in $\mathrm{BeCl}_{2}$ and $\mathrm{MgCl}_{2}$

In the light of the above statements, choose the correct answer from the options given below :

$\mathrm{(A)}$ is true but $(\mathrm{R})$ is false

Both (A) and $(\mathrm{R})$ are true and $(\mathrm{R})$ is the correct explanation of $(A)$

(A) is false but (R) is true

Both (A) and (R) are true but (R) is NOT the correct explanation of (A)

JEE Main 2023 (Online) 13th April Evening Shift

MCQ (Single Correct Answer)

-1

Out of Syllabus

Better method for preparation of $$\mathrm{BeF}_{2}$$, among the following is :

$$\mathrm{BeH}_{2}+\mathrm{F}_{2} \stackrel{\Delta}{\longrightarrow} \mathrm{BeF}_{2}$$

$$\left(\mathrm{NH}_{4}\right)_{2} \mathrm{BeF}_{4} \stackrel{\Delta}{\longrightarrow} \mathrm{BeF}_{2}$$

$$\mathrm{Be}+\mathrm{F}_{2} \stackrel{\Delta}{\longrightarrow} \mathrm{BeF}_{2}$$

$$\mathrm{BeO}+\mathrm{C}+\mathrm{F}_{2} \stackrel{\Delta}{\longrightarrow} \mathrm{BeF}_{2}$$

JEE Main 2023 (Online) 13th April Evening Shift

MCQ (Single Correct Answer)

-1

Out of Syllabus

Identify the correct order of standard enthalpy of formation of sodium halides :

$$\mathrm{NaI}<\mathrm{NaBr}<\mathrm{NaCl}<\mathrm{NaF}$$

$$\mathrm{NaI}<\mathrm{NaBr}<\mathrm{NaF}<\mathrm{NaCl}$$

$$\mathrm{NaF}<\mathrm{NaCl}<\mathrm{NaBr}<\mathrm{NaI}$$

$$\mathrm{NaCl}<\mathrm{NaF}<\mathrm{NaBr}<\mathrm{NaI}$$

JEE Main 2023 (Online) 13th April Morning Shift

MCQ (Single Correct Answer)

-1

Out of Syllabus

$$\mathrm{Be}(\mathrm{OH})_{2}$$ reacts with $$\mathrm{Sr}(\mathrm{OH})_{2}$$ to yield an ionic salt.

Choose the incorrect option related to this reaction from the following :

Be is tetrahedrally coordinated in the ionic salt.

The element $$\mathrm{Be}$$ is present in the cationic part of the ionic salt.

Both $$\mathrm{Sr}$$ and $$\mathrm{Be}$$ elements are present in the ionic salt.

The reaction is an example of acid - base neutralization reaction.

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