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This is a Long Answer Type Questions as classified in NCERT Exemplar

Explanation- total energy of electron

E= $\frac{\mu Z^2{e}^4}{8{\epsilon }_o^2{h}^2}\frac{1}{n^2}$

The frequency hv= $\frac{\mu e^4}{8{\epsilon }_o^2{h}^2}\left(1-\frac{1}{4}\right)=\frac{\mu e^4}{8{\epsilon }_o^2{h}^2}\frac{3}{4}$

$?\lambda$ = ${\lambda }_D-{\lambda }_H$

$100\times \frac{?\lambda }{{\lambda }_H}$ = $\frac{{\lambda }_D-{\lambda }_H}{{\lambda }_H}\times 100$ = $\frac{{\mu }_D-{\mu }_H}{{\mu }_H}\times 100$

= $\frac{\frac{m_{e{M}_D}}{m_e+M_H}-\frac{m_{e{M}_D}}{m_e-M_H}}{\frac{m_{e{M}_D}}{m_e+M_H}}\times 100$

When m_e<H<

after solving we get 2.714 $\times {10}^{-2}\%$

This is a Short Answer Type Questions as classified in NCERT Exemplar

The electronic configuration of Na is [Ne]3s¹ while that of Mg is [Ne]3s² as Mg possesses a fully filled 3s orbital thus its first ionisation enthalpy is higher than that of Na.

After losing one electron Na obtained the electronic configuration of Ne while Mg acquired the electronic configuration of Na thus the second ionisation energy of Na is higher than that of Mg.

This is a Long Answer Type Questions as classified in NCERT Exemplar

Explanation- as we know total energy in stationary orbit is

E_n=- $\frac{{-me}^4}{8n^2{{\epsilon }_0}^2{h}^2}$  where sign have usual meaning.

According to bohr third postulate h $\nu =E_{f-}{E}_i$

$\nu =$ - $\frac{{me}^4}{8{{\epsilon }_0}^2{h}^3}(\frac{1}{n_f^1}-\frac{1}{n_i^2})$

$\lambda \propto \frac{1}{\propto }$

Where $\propto$  is the reduced mass

Reduced mass for H=_H=;m_e(1-m_e/M)

D= _D; m_e(1-m_e/2M)

 =m_e(1-m_e/2M)(1+m_e/2M)

If for hydrogen deuterium, the wavelength

$\frac{{\lambda }_D}{{\lambda }_H}=\frac{{\propto }_H}{{\propto }_D}$ = (1+ $\frac{m_e}{2M}$ )^-1= (1- $\frac{1}{2\times 1840}$ )

${\lambda }_D={\lambda }_H\times 0.99973$  so lines emitted are 1217.7A⁰,1027.7A⁰,974.04A⁰

This is a Short Answer Type Questions as classified in NCERT Exemplar

In the p block, some elements are metallic some elements are non-metallic while some elements are metalloids in nature. The oxides of metals are basic in nature and that of oxides of nonmetals are acidic in nature.

Acidic oxide SO₂ + H₂O →H₂SO₃

Basic oxide  Tl₂O + 2HCl → 2TlCl +H₂O

Amphoteric oxide

Al₂O₃ + 6HCl → 2AlCl₃ + 3H₂O

Al₂O₃ +2 NaOH → 2NaAlO₂ + H₂O

Reaction with water

B₃O₂ +3H₂O → 2H₃BO₃

P₄O₁₁  + 6H2O  → 4H₄PO₃

Cl₂ O₇ + H2O → HClO₄

The MBSE HSSLC official mark sheet issued by the Board will be given by the school to the students. The exact date and time of collecting the MBSE HSSLC mark sheet will be informed to the students. Students have to collect the MBSE HSSLC mark list from the schools. They should verify the MBSE HSSLC mark sheet.

This is a Short Answer Type Questions as classified in NCERT Exemplar

The anomalous behaviour of the first member of each group of representative elements i.e. of second period can be attributed to their small size, high charge/radius ratio, high electronegativity and absence of vacant d-orbitals to expand their oxidation state.The first member of each group of p-Block elements displays their greater ability to form multiple bond with itself, e.g. C=C, O=O, N=N and to other second periodic elements, e.g. C=O, C=N, N=N.

This is a Short Answer Type Questions as classified in NCERT Exemplar

The N possesses a half filled p-orbital which provides it extra stability due to symmetry due to which its electron gain enthalpy is positive and its ionization enthalpy is larger than that of O.

Simple Present Tense Rule:

Subject + base verb (s/es for he/she/it)

Example: She goes to college.

Shows habit, facts, and routines.

Present Continuous Tense Rule:

Subject + is/am/are + verb-ing

Example: She is going to college.

Shows actions happening now or temporary actions.

This is a Short Answer Type Questions as classified in NCERT Exemplar

Option (i)

As across the period the atomic radius decreases due to the increase of effective nuclear charge.

This is a Short Answer Type Questions as classified in NCERT Exemplar

The characteristics properties of p-block elements are as follows:-

(i) It contain metals, nonmetals and metalloids

(ii) Mostly involved in covalent bonding

(iii) Some elements show variable oxidation state

(iv) It possesses relatively higher ionization enthalpy compared to the s-block elements.

To enroll for course admission at IEM Kolkata, candidates must complete the basic eligibility criteria set by the college. For UG courses, students must have to complete Class 12 and for PG course, aspirants must complete graduation. Check the table below for more clarity:

To get admission to UG courses at IEM Kolkata, aspirants need to complete Class 12, and for PG course, students must have completed their graduation. Check the table provided below for more information- 

This is a Short Answer Type Questions as classified in NCERT Exemplar

(i) C has the highest ionization energy among the given elements as along the period ionization enthalpy increases whereas it decreases down the group.

(ii) Al is the most metallic element among the given elements because down the group metallic character increases

The rule of Present Continuous Tense in English Grammar is:

Subject + am/is/are + verb-ing + Object

Examples:

• I am playing.
• He is writing a letter.
• They are watching TV.

This is a Short Answer Type Questions as classified in NCERT Exemplar

To identify the Present Continuous Tense in a sentence, follow these three steps:

1. Check if there is 'is/am/are' in the sentence.
2. Check for the –ing form of verb.
3. Lastly, confirm that the sentence is describing an action happening right now, a temporary ongoing action, or a future action.

To get admission to IEM Kolkata, students must meet the basic eligibilty criteri and qualify for the relevant entrance exam. Check below the detailed admission criteria for IEM Kolkata:

The Present Continuous Tense is used in three cases:

Case 1: Actions happening right now

Examples:

• She is talking on the phone.
• We are ordering Pizza from Dominos for lunch.

Case 2: Temporary or ongoing actions

Examples:

• I am staying at my friend's house for a few days.
• She is going to Decathlon to buy a winter jacket.

Case 3: Future planned events (with a specific time frame)

Example:

• They are having a cricket match this Sunday.
• He is flying to London next week.