Pearson | PTE
Register now for PTE & Unlock 20% OFF : Use promo code: 'C360SPL20'. Valid till 30th NOV'24! Trusted by 3,500+ universities globally
The Joint Entrance Examination (JEE) Main is conducted by the National Testing Agency (NTA), and every year, lakhs of students appear for the exam. It is the entrance test – or the preliminary selection round – for the top engineering colleges in the country including the Indian Institutes of Technology (IIT), National Institutes of Technology (NIT), Indian Institutes of Information Technology (IIIT) and many more government institutions.
New: Direct link to apply for JEE Main 2025 registration for session 1
Also Check: Crack JEE Main 2025 - Join Our Free Crash Course Now!
JEE Main 2025: Sample Papers | Syllabus | Mock Tests | PYQs | Video Lectures
JEE Main 2025: Preparation Guide | High Scoring Topics | Study Plan 100 Days
Clearly, JEE Main is critical. However, JEE Main 2021 had questions which were conceptually or factually ambiguous and some of them were simply incorrect, going by the JEE Main answer key. Last year, the exam was conducted in four phases – February, March, July and August – across 26 Shifts. The result was declared in September.
Here, Careers360 looks into the questions asked in the July and August shifts, and highlights some of the errors in the JEE Main previous year question paper’s Chemistry section. The necessary changes required for these questions were absent from the NTA JEE Main answer keys, which could have affected the scorecards of many candidates in the JEE Main result.
These questions, along with their respective problems, are listed out below:
Question ID : 86435117255
JEE Main Answer Key: 172
The issue:
The unit in which Kp is to be reported has not been specified in the question.
So, a student solving for the unit as (Pa)-1 will get an answer of 0.172 which would be rounded off to 0 while the given answer will be in units of (kPa)-1
____________________________________________________________________________
Question ID : 86435117528
JEE Main Answer Key: 1
The issue:
There is a conceptual error in the question. A negatively-charged sol cannot be precipitated by a negatively-charged ion.
Also, the coagulating value is defined as the minimum concentration of an electrolyte in millimoles per litre required to cause precipitation of a sol in two hours.
So, there arises another problem: How do you extrapolate data for two hours from the one-hour data?
____________________________________________________________________________
Question ID : 86435117785
JEE Main Answer Key: 86435159952 (Option 2)
Question and Option IDs
The issue:
Multiple options given in the question (Options 1,2 and 3) are capable of forming tertiary alcohol on reaction with excess of Grignard reagent (CH3MgBr) followed by hydrolysis.
Option 1: Alpha- Beta unsaturated carbonyl compounds show direct addition to the carbonyl group with Grignard reagent. Hence, tertiary alcohols will be obtained from the carbonyl groups
Option 3: Grignard reagent can add to a ketone, forming a tertiary alcohol.
____________________________________________________________________________
Question ID : 86435118234
JEE Main Answer Key: 86435161299 (Option 1)
The issue:
Lewis acids are not used with Phenol because Phenol itself forms a complex with the Lewis acid, due to which the ring becomes deactivated towards Electrophilic Substitution.
In fact, this reaction of Phenol with a Lewis acid FeCl3 is actually used to detect the presence of Phenol in solution. Phenol forms a complex with neutral FeCl3 and produces a violet colour.
Correct answer should be 86435161298 [Option (3)]
____________________________________________________________________________
Question ID : 86435118225
JEE Main Answer Key: 86435161264 (Option 3)
The issue:
Be is not an alkaline earth metal as its oxide and hydroxide are Amphoteric in nature.
Here is an excerpt from NCERT textbook’s chapter on the s Block elements confirming it.
Hence, Statement I is also correct in the given question.
Correct answer should be 86435161261 [Option (2)]
____________________________________________________________________________
Question ID : 86435118870
JEE Main Answer Key: 5
The issue:
Data given is insufficient to solve the problem.
Molality (m) can be calculated from the density of solution only when the Molarity (M) is also given in the question.
In the question, Molarity has not been provided and thus the question cannot be solved.
____________________________________________________________________________
Question ID : 86435119236
JEE Main Answer Key: 300
The issue :
The answer in the JEE Main final answer key was wrong. The answer should have been 600.
____________________________________________________________________________
Question ID : 86435120226
JEE Main Answer Key: 50
The issue :
The answer given in the answer key is wrong. The answer should be 0.
The answer is 0.02 which would be rounded off to 0.
For the answer to be 50, the value of (Kc)-1 had to be asked.
____________________________________________________________________________
Question ID : 86435120586
JEE Main Answer Key: 4
The issue :
The answer given is 4 because the inner 4f electrons have not been counted.
The question does not say that we need to consider only the 5f electrons
____________________________________________________________________________
Question ID : 86435121290
JEE Main Answer Key: 86435170463 (Option 4)
The issue :
Alcoholic NaOH causes dehydrohalogenation (elimination) and not substitution.
The answer should be 86435170462 (Option 2)
____________________________________________________________________________
Question ID : 86435121287
JEE Main Answer Key: 86435170452 (Option 2)
The issue :
None of the options is correct.
All the given options contain permanganate ion (MnO4-) which contains Mn in its highest oxidation state (+7) and hence, it cannot show disproportionation reaction
Question should have been awarded as bonus
____________________________________________________________________________
Question ID : 86435121562
JEE Main Answer Key: 86435171281 (Option 4)
The issue :
Options 1 and 4 can both be correct but only Option 4 has been given as the correct answer.
Acenaphthene (compound in Option 1) is also Aromatic in nature.
____________________________________________________________________________
Apart from the above-mentioned questions, there were also some in the integer section that had very lengthy mathematical calculations and whose answers had to be rounded off to the nearest integers.
These questions are usually solved by approximations and it is very difficult for students to arrive at the correct integer answer. Previously, these questions had a correct range for the answer, which gave students some leeway to make appropriate approximations in calculations.
Now, with negative marking in the numerical response questions, this becomes an even bigger problem. Considering the high-stakes nature of the JEE Mains, even a few such errors can have significant ramifications for applicants and be deeply demoralising.
Application Date:03 September,2024 - 31 December,2024
Application Date:16 September,2024 - 04 December,2024
Hello,
For downloading JEE Main 2025 sample papers, you can access them from various educational resources that provide free or structured content:
Careers360 lists sample and past JEE papers with solutions available for download, which can be very useful for targeted preparation.
To download sample papers with solution, visit : https://engineering.careers360.com/articles/jee-main-sample-papers
Hope it helps !
Hello,
To view the available books and study materials for specific exams like JEE Main or JEE Advanced on Careers360, follow these steps:
Navigate to the Careers360 Website : Visit Careers360 and use their search function to locate resources for JEE Main, JEE Advanced, or other exams.
Explore the Study Material Section : Careers360 provides detailed lists of e-books, sample papers, and study guides. For instance, for JEE Main, you can find:
Filters and Categories : Use filters on the site to narrow down books by type (e.g., question papers, study guides), education level, or specific topics relevant to JEE Main or JEE Advanced.
Free and Paid Options : Careers360 offers both free downloads and premium study packages. The "JEE Main Knockout Programme," for example, includes comprehensive resources such as video lectures and expert guidance.
For quick access, you can directly search for study material for a given exam on the Careers360 site, ensuring you stay updated with the latest editions and resources.
To get study material, visit :
1. https://engineering.careers360.com/articles/best-books-for-jee-main
2. https://engineering.careers360.com/download/jee-main-ebooks
Hope it helps !
hello,
To start JEE Main preparation, allocate 6–8 hours daily. Focus on Physics, Chemistry, and Maths equally. Study in blocks of 2 hours with breaks. Morning: Revise concepts and solve NCERT questions. Afternoon: Practice numericals and past papers. Evening: Attempt mock tests or solve advanced problems. Dedicate Sundays to full-length mock tests and analysis. Ensure 7 hours of sleep and daily exercise. Adjust based on your school/college timings.
You can check out the link below for a detailed schedule
https://engineering.careers360.com/articles/how-prepare-for-jee-main-in-6-months
Hello Aastha,
Yes, it's okay to use your mother's name as per the Aadhaar card, "Mamta Walia," while filling out the JEE application form. However, during document verification or counseling, there could be a discrepancy between the 10th marksheet and Aadhaar card. To avoid future issues, keep an affidavit or a notarized document ready explaining the name difference, or get it corrected in either document if possible.
For more details, you can check out an article by Careers360 whose link is given below:
Link: https://engineering.careers360.com/articles/how-to-fill-jee-main-application-form
I hope this answer helps you. If you have more queries then feel free to share your questions with us we will be happy to assist you.
Thank you and wishing you all the best for your bright future.
Hello aspirant,
According to the most recent NTA announcement about the JEE Main 2025 application form correction feature, candidates will not be able to change their uploaded photo if it was originally submitted incorrectly.
So you can change your photo in JEE MAINS correction window.
Thank you
A flight attendant is a professional whose primary duty is to ensure the safety and comfort of passengers during an airline flight. An individual who is pursuing a career as a flight attendant is part of the cabin crew for the plane, a team of personnel who operate a commercial, business, or even military aircraft while travelling domestically or internationally.
An individual pursuing a career as a flight attendant is specially trained for the aircraft in which he or she works since passenger safety is their foremost concern. In this article, we will discuss how to become a flight attendant in India or how to become a flight attendant after graduation.
An aerospace engineer is an individual who develops new ideas and technologies that can be used in defence systems, aviation, and spacecraft. He or she not only designs aircraft, spacecraft, satellites, and missiles but also creates test vehicles to ensure optimum functionality. Aerospace engineering is a branch of engineering that deals with the study, design, and development of aerial vehicles such as aircraft and spacecraft.
Aerospace engineering jobs deal with employees who design or build missiles and aircraft for national defence, or spacecraft. Aerospace engineering or aircraft engineering is often referred to as rocket science. The bottom line is that the person who is pursuing a career in aerospace engineering has to deal with multiple teams at different levels and work across various technologies.
A career in the aviation industry always sounds exciting. But, there is no scope for the slightest error as it may cost the lives of many people. A Flight Engineer role comes with the responsibility of monitoring the aircraft engine and control systems while in flight. Whenever the aircraft is away from the home station, he or she is required to perform pre-flight and post-flight inspections
An aircrew officer or airline commanders fly aircraft to provide transportation to passengers or cargo. The aircrew officer operates the engines of aircraft and controls to navigate and fly the airplane. The ability to learn new technologies every time and to stay up-to-date with the changes in the industry is what the aircrew officer should possess.
This could be possible through membership with professional pilot associations. The aircrew officer is also one of the highest-paid professionals and the job is quite coveted. Keep reading to find out what you need to know about how to become aircrew officer.
You may also read career as Airline Pilot.
An air hostess is a flight attendant also known as a cabin crew or steward. An air hostess undertakes several pre-flight, in-flight, and post-flight duties and is responsible for ensuring the safety and comfort of passengers on both national and international flights. A career as an air hostess might be desirable for you if you are excited about a job in which you can help people and travel to exciting places.
Air hostesses play a crucial role in the flight crew, working closely with pilots and ground personnel to provide a safe and comfortable travel experience, even beyond their hospitality responsibilities. Being flexible, having strong communication skills, and being dedicated to the comfort of passengers are all necessary for their dynamic function, which makes them essential to the entire travel experience.
An Aeronautical Engineer job comes with the responsibility of designing aircraft and thrust systems. He or she is employed in aviation, defence or civil aviation industries. Aeronautical Engineer is generally engaged in the design of aircraft and propulsion systems as well as the analysis of building materials and aircraft's aerodynamic performance. The role of an Aeronautical Engineer may involve assembling parts of aircraft, testing and maintaining them.
A Safety Manager is a professional responsible for employee’s safety at work. He or she plans, implements and oversees the company’s employee safety. A Safety Manager ensures compliance and adherence to Occupational Health and Safety (OHS) guidelines.
Are you searching for an 'airline pilot job description'? An airline pilot or airline commander flies aircraft and helicopters to provide transportation to passengers or cargo. The airline pilot operates the engines of the aircraft and controls them to navigate and fly the airplane. The ability to learn new technologies every time and to stay up-to-date with the changes in the industry is what aviators should possess. The career as airline pilot is also one of the highest-paid professionals and the job is quite coveted.
Welding Engineer Job Description: A Welding Engineer work involves managing welding projects and supervising welding teams. He or she is responsible for reviewing welding procedures, processes and documentation. A career as Welding Engineer involves conducting failure analyses and causes on welding issues.
A career as Transportation Planner requires technical application of science and technology in engineering, particularly the concepts, equipment and technologies involved in the production of products and services. In fields like land use, infrastructure review, ecological standards and street design, he or she considers issues of health, environment and performance. A Transportation Planner assigns resources for implementing and designing programmes. He or she is responsible for assessing needs, preparing plans and forecasts and compliance with regulations.
Individuals who opt for a career as an environmental engineer are construction professionals who utilise the skills and knowledge of biology, soil science, chemistry and the concept of engineering to design and develop projects that serve as solutions to various environmental problems.
A Safety Manager is a professional responsible for employee’s safety at work. He or she plans, implements and oversees the company’s employee safety. A Safety Manager ensures compliance and adherence to Occupational Health and Safety (OHS) guidelines.
A Conservation Architect is a professional responsible for conserving and restoring buildings or monuments having a historic value. He or she applies techniques to document and stabilise the object’s state without any further damage. A Conservation Architect restores the monuments and heritage buildings to bring them back to their original state.
A Structural Engineer designs buildings, bridges, and other related structures. He or she analyzes the structures and makes sure the structures are strong enough to be used by the people. A career as a Structural Engineer requires working in the construction process. It comes under the civil engineering discipline. A Structure Engineer creates structural models with the help of computer-aided design software.
Highway Engineer Job Description: A Highway Engineer is a civil engineer who specialises in planning and building thousands of miles of roads that support connectivity and allow transportation across the country. He or she ensures that traffic management schemes are effectively planned concerning economic sustainability and successful implementation.
Are you searching for a Field Surveyor Job Description? A Field Surveyor is a professional responsible for conducting field surveys for various places or geographical conditions. He or she collects the required data and information as per the instructions given by senior officials.
Individuals who opt for a career as geothermal engineers are the professionals involved in the processing of geothermal energy. The responsibilities of geothermal engineers may vary depending on the workplace location. Those who work in fields design facilities to process and distribute geothermal energy. They oversee the functioning of machinery used in the field.
A geologist attempts to comprehend the historical backdrop of the planet we live on, all the more likely to anticipate the future and clarify current events. He or she analyses the components, deployments, results, physical characteristics, and past of the planet. A geologist examines the landforms and landscapes of the earth in relation to the geology, climatic, and human processes that have shaped them.
A geologist studies earth procedures, for example, seismic tremors, avalanches, floods, and volcanic eruptions to review land and draw up safe structure plans. When he or she researches earth materials, explores metals and minerals, yet in addition search for oil, petroleum gas, water, and strategies to extricate these.
Energy efficiency engineering is a broad field of engineering which deals with energy efficiency, energy services, facility management, plant engineering, and sustainable energy resources. Energy efficiency engineering is one of the most recent engineering disciplines to emerge. The field combines the knowledge and understanding of physics, chemistry, and mathematics, with economic and environmental engineering practices. The main job of individuals who opt for a career as an energy performance engineer is to find the most efficient and sustainable path to operate buildings and manufacturing processes.
Individuals who opt for a career as energy performance engineers apply their understanding and knowledge to increase efficiency and further develop renewable sources of energy. The energy efficiency engineers also examine the use of energy in those procedures and suggest the ways in which systems can be improved.
A career as a Petroleum engineer is concerned with activities related to producing petroleum. These products can be in the form of either crude oil or natural gas. Petroleum engineering also requires the exploration and refinement of petroleum resources. Therefore, a career as a petroleum engineer comes up with oil and gas onshore jobs. There are also desk jobs in the petroleum industry. In layman’s terms, a petroleum engineer is a person who finds the best way to drill and extract oil from oil wells. Individuals who opt for a career as petroleum engineer also tries to find new ways to extract oil in an efficient manner.
A career as Transportation Planner requires technical application of science and technology in engineering, particularly the concepts, equipment and technologies involved in the production of products and services. In fields like land use, infrastructure review, ecological standards and street design, he or she considers issues of health, environment and performance. A Transportation Planner assigns resources for implementing and designing programmes. He or she is responsible for assessing needs, preparing plans and forecasts and compliance with regulations.
A career as a civil engineer is of great importance for the infrastructural growth of the country. It is one of the most popular professions and there is great professional as well as personal growth in this civil engineering career path. There is job satisfaction in this civil engineering career path, but it also comes with a lot of stress, as there are multiple projects that need to be handled and have to be completed on time. Students should pursue physics, chemistry and mathematics in their 10+2 to become civil engineers.
A career as a Transportation Engineer is someone who takes care of people's safety. He or she is responsible for designing, planning and constructing a safe and secure transportation system. The transportation sector has seen a huge transformation and is growing day by day and improving every day.
As a Transport Engineer, he or she needs to solve complex problems such as accidents, costs, traffic flow, and statistics. A Transport Engineer also collaborates for projects with some other companies.
A loco pilot or locomotive pilot is a professional responsible for operating trains. He or she starts, stops, or controls the speed of the train. A locomotive pilot ensures that the train operates according to time schedules and signals. These loco pilots are responsible for carrying people and products to distinct destinations.
A loco pilot has thorough knowledge and understanding of the railway operations, rules, regulations, protocols, and measures to take in times of emergency. Their role is crucial in ensuring passenger and freight trains' smooth and safe operation. Here, in this article, we will discuss everything on how to how to become a loco pilot.
Ranked #42 among Engineering colleges in India by NIRF | Highest CTC 50 LPA , 100% Placements
60+ Years of Education Legacy | UGC & AICTE Approved | Prestigious Scholarship Worth 6 Crores | H-CTC 35 LPA
India's youngest NAAC A++ accredited University | NIRF rank band 151-200 | 2200 Recruiters | 45.98 Lakhs Highest Package
India's Largest University | NAAC A++ Accredited | 100% Placement Record | Highest Package Offered : 3 Cr PA
Hands on Mentoring and Code Coaching | Cutting Edge Curriculum with Real World Application
Register now for PTE & Unlock 20% OFF : Use promo code: 'C360SPL20'. Valid till 30th NOV'24! Trusted by 3,500+ universities globally