default_background
✕

Find the best tutors and institutes for Class 12 Tuition

Find Best Class 12 Tuition

Please select a Category.

Please select a Locality.

No matching category found.

No matching Locality found.

Q13.6:
Suppose, we think of fission of a \(^{56}_{26}Fe\) nucleus into two equal fragments, \(^{28}_{13}Al\). Is the fission energetically possible? Argue by working out Q of the process. Given \(m (\(^{56}_{26}Fe\)) = 55.93494 u\) and \(m (\(^{28}_{13}Al\)) = 27.98191 u\).

Solution :

Step 1: Define the Nuclear Reaction and Q-Value

The nuclear fission process is represented as:

$^{56}_{26}\text{Fe} \rightarrow ^{28}_{13}\text{Al} + ^{28}_{13}\text{Al} + Q$

The energy released (or required) in a nuclear reaction is determined by the mass defect, defined as the difference between the mass of the reactants and the mass of the products [Per Einstein’s mass-energy equivalence principle, $Q = (\Delta m)c^2$].

Step 2: Calculate the Mass Defect ($\Delta m$)

The mass defect is given by the formula:

$\Delta m = [m(^{56}_{26}\text{Fe}) - 2 \times m(^{28}_{13}\text{Al})]$

Given values:

  • $m(^{56}_{26}\text{Fe}) = 55.93494 \text{ u}$
  • $m(^{28}_{13}\text{Al}) = 27.98191 \text{ u}$

Substitute the values into the equation:

$\Delta m = 55.93494 \text{ u} - 2 \times (27.98191 \text{ u})$

$\Delta m = 55.93494 \text{ u} - 55.96382 \text{ u}$

$\Delta m = -0.02888 \text{ u}$

Step 3: Calculate the Q-Value in MeV

To convert the mass defect in atomic mass units (u) to energy in MeV, we use the conversion factor $1 \text{ u} \approx 931.5 \text{ MeV/c}^2$ [Based on the energy equivalent of one atomic mass unit].

$Q = \Delta m \times 931.5 \text{ MeV/u}$

$Q = -0.02888 \text{ u} \times 931.5 \text{ MeV/u}$

$Q \approx -26.9 \text{ MeV}$

Step 4: Energetic Analysis

Since the calculated $Q$ value is negative ($Q < 0$), the reaction is endothermic [Per the Laws of Thermodynamics regarding energy balance in nuclear systems]. This implies that energy must be supplied to the system for the fission to occur; it does not happen spontaneously nor does it release energy.

Initial State: 56-Fe (55.93494 u) Energy Input Required: 26.9 MeV Final State: 2 x 28-Al (55.96382 u)

Final Solution: The fission of $^{56}_{26}\text{Fe}$ into two $^{28}_{13}\text{Al}$ fragments is not energetically possible because the Q-value is $-26.9 \text{ MeV}$, indicating that the process is endothermic and requires an external energy input of 26.9 MeV to proceed.


More Questions from Class 12 Physics Nuclei EXERCISES


CBSE Solutions for Class 12 Physics Nuclei


Chapters in CBSE - Class 12 Physics


Top Tutors who teach Nuclei

(5)
Top Tutor
locationImg HSR Layout, Bangalore
experience 7 yrs of Exp students 2 students
rsIcon 500 per hour
Certified tutor with 7 years of experience
Online Classes Online Classes

I am an experienced, qualified teacher and tutor with over 4 years of experience in teaching Maths,Physics and Chemistry, across different boards including CBSE, ICSE, IGCSE and State Board. Passionate about solving mathematical problems and chemical equations, over the years I have helped hundreds of students overcome their fear of Maths,Physics and Chemistry. So far, I have worked as a Full Time Tutor and guided over 189 students reach their goals in the respective subjects

Skills: Mathematics , Physics and more
Also teaches: BCom Tuition, Class 10 Tuition and more

(20)
Top Tutor
locationImg Sector 10, Dwarka, Delhi
experience 6 yrs of Exp students 5 students
greenClock 535 hrs of classes completed
rsIcon 480 per hour
English Tutor with 8 years experience
Online Classes Online Classes

I am (English Educator). I've been teaching for more than 8 years. My background includes planning and teaching English to children as well as adults. I have worked with UNACADEMY, Chandigarh University, Mahendras and many more institutions. I got certified as a Meet & Greet officer, conforming to National Skill Qualifications Framework Level-4. Two times winner in Declamation contest at the college level

Kajal

Her teaching is nice and she's friendly too. Her lessons were engaging, useful, and she is very patient with everyone in class.

Skills: English

(9)
Top Tutor
locationImg Rajouri Garden, Delhi
experience 10 yrs of Exp students 1 student
greenClock 8 hrs of classes completed
rsIcon 1200 per hour
PGT Economics & Accountancy with more than 10 years of experience
Online Classes Online Classes
homeTutions Student's Home
regularClasses Tutor's home

I believe in delivering concepts and knowledge from the scratch so as to make the subject easy and relatable. My target is not only marks but rather developing an interest in the students for the subjects so as to have a better understanding and a good prospect for the future.

Skills: Economics , Accounts and more
Also teaches: Class 11 Tuition

Gaurav Puri Class 12 Tuition trainer in Faridabad
(113)
Top Tutor
locationImg Sector-10, Faridabad
experience 20 yrs of Exp students 7 students
greenClock 173 hrs of classes completed
rsIcon 700 per hour
Make Accounts Eazy & Interesting With GP Sir With 23 Yrs Of Expertise
Online Classes Online Classes

I am a dedicated and experienced educator specializing in Accountancy & Business Studies with extensive experience teaching senior secondary students, particularly Classes XII, I focus on building strong conceptual understanding and practical problem-solving skills. My teaching approach is student-centric, combining clear explanations, regular practice, revisions, and exam-oriented preparation. I believe in maintaining discipline while creating a comfortable environment where students can ask questions freely. I closely monitor each student's progress and provide additional support wherever needed. My goal is not only to help students achieve excellent academic results but also to develop confidence and a genuine understanding of the subjects.

Mohak Bhatia

Puri academic classes are good for class 12 accountancy for any student. It was a great experience with sir.

Skills: Accounts
Also teaches: MCom Tuition, BBA Tuition and more

(15)
superTutorSuper Tutor
locationImg Sector-85, Faridabad
experience 20 yrs of Exp students 5 students
greenClock 170 hrs of classes completed
rsIcon 750 per hour
A science graduate with more than 35 years experience
Online Classes Online Classes
regularClasses Tutor's home

Have been teaching maths cbse since last 35 years and still favourite among my students.

Arush Verma

They teach you very well. Let's clarify each and every concept. Let's take a regular test. Chapter-wise assignments are provided. They give extra time.

Skills: Mathematics
Also teaches: Class 9 Tuition, Class 10 Tuition and more

Other Subjects in CBSE - Class 12

Worksheet Icon

Download free CBSE - Class 12 Physics Nuclei EXERCISES worksheets

Download Now

Find Best Class 12 Tuition ?

Find Now »