Neeraj Anand, Param Anand

Anand Classes provides a clear and detailed explanation of the variation of ionization enthalpy down a group in the periodic table, an important topic for JEE, NEET, and CBSE Class 11 Chemistry. As we move from the top to the bottom of a group, ionization enthalpy gradually decreases due to factors such as an increase in atomic size, an increase in the shielding effect, and a relatively smaller impact of increasing nuclear charge. Understanding this periodic trend helps students predict the chemical reactivity, metallic character, and bonding nature of elements, making it a crucial concept for competitive exams and board preparation.

Anand Classes presents detailed study material on Ionization Enthalpy (Periodic Table) Class 11 Important Conceptual NCERT Question Answers for JEE, NEET, and CBSE Board students. Ionization enthalpy is a fundamental periodic property that explains the energy required to remove an electron from an isolated gaseous atom. Understanding this concept not only strengthens your basics of atomic structure but also helps in solving higher-order conceptual and numerical problems. In this article, you will find well-explained answers to NCERT questions, along with extra tips, solved examples, and exam-oriented insights.

Anand Classes brings you a clear and detailed explanation of Electron Gain Enthalpy (Electron Affinity), an important concept in Chemistry for JEE, NEET, and CBSE Class 11 students. Electron gain enthalpy is defined as the energy change that occurs when an electron is added to an isolated gaseous atom to form a negatively charged ion. Understanding this concept helps students grasp the reactivity trends of elements, periodic variations, and the stability of ions, making it a crucial topic for competitive exams.

Anand Classes brings you a detailed explanation of the important topic Factors Affecting Electron Gain Enthalpy for JEE, NEET, and CBSE Class 11 Chemistry. Electron gain enthalpy refers to the energy change when an isolated gaseous atom gains an extra electron to form a negative ion. Understanding how nuclear charge, atomic size, electronic configuration, and shielding effect influence electron gain enthalpy is crucial for mastering periodic trends and solving exam-based questions. This article provides clear theory, examples, FAQs, and comparisons to help students build strong conceptual clarity and score high in competitive as well as board examinations.

Anand Classes provides the best study material for JEE, NEET, and CBSE students. In this article, we explain one of the most important periodic properties – Electron Gain Enthalpy. It refers to the energy change when an atom gains an extra electron to form a negative ion. Understanding the periodic trends of electron gain enthalpy (variation across a period and down a group) is crucial for competitive exams like JEE Main, JEE Advanced, NEET, and Board examinations, as it helps in predicting the reactivity and chemical behavior of elements.

Anand Classes brings you a detailed explanation of why halogens have the highest negative electron gain enthalpies in the periodic table. Halogens (Group 17 elements) like fluorine, chlorine, bromine, iodine, and astatine possess the electronic configuration ns²np⁵, which makes them just one electron short of achieving the stable noble gas configuration. This unique property gives halogens a very strong tendency to accept an additional electron, releasing a large amount of energy in the process. As a result, their electron gain enthalpies are highly negative, a key concept often asked in JEE, NEET, and CBSE Class 11 Chemistry exams.

Anand Classes explains the concept of electron gain enthalpy of noble gases, beryllium (Be), magnesium (Mg), nitrogen (N), and phosphorus (P) in detail for JEE, NEET, and CBSE examinations. While most elements have negative electron gain enthalpy due to their tendency to attract electrons, noble gases exhibit positive electron gain enthalpy because of their stable octet configuration (ns2np6). On the other hand, Be and Mg with completely filled s-orbitals, and N and P with half-filled p-orbitals, show very low or nearly zero electron gain enthalpy values due to their extra stability. Understanding these exceptions is crucial for mastering trends in the periodic table and is a frequently asked concept in competitive exams.

Anand Classes explains the important concept of electron gain enthalpy of halogens in a simple yet detailed way for JEE, NEET, and CBSE students. The trend of electron gain enthalpy in halogens (F, Cl, Br, I, At) is an essential topic of the periodic table, often asked in competitive exams. While generally electron gain enthalpy becomes less negative down the group, fluorine shows an anomaly where its value is less negative than chlorine. Understanding this exception, along with the overall trend, helps students strengthen their grasp on periodic properties and improve exam performance.

Anand Classes explains that the electron gain enthalpy of second-period elements (such as N, O, F) is generally less negative than their third-period counterparts (such as P, S, Cl). This trend arises because second-period elements are very small in size, and when an extra electron is added, it experiences strong electron–electron repulsions in the compact 2p orbitals. In contrast, third-period elements have larger atomic sizes and more diffused orbitals, so the incoming electron experiences less repulsion and greater attraction from the nucleus, resulting in more negative electron gain enthalpy values. This concept is important for JEE, NEET, and CBSE Class 11 Chemistry as it explains anomalies in periodic trends.

Anand Classes explains that successive electron gain enthalpies (EA₁, EA₂) represent the energy changes when one or more electrons are added to a gaseous atom. The first electron gain enthalpy (EA₁) is usually negative because a neutral atom attracts the incoming electron and energy is released. However, the second electron gain enthalpy (EA₂) is always positive, since the electron is being added to a negatively charged ion and experiences strong Coulombic repulsion, requiring external energy input. For example, in oxygen, EA₁ = –141 kJ mol⁻¹ (energy released), while EA₂ = +780 kJ mol⁻¹ (energy absorbed).