Answer: (b) F > O > Cl > N During a period, as we move from left to right, the non-metallic characteristics of the elements become more prominent. As a result, F > O > N.
Answer: c) F > N > C > B > Si While moving from left to right in a period, the nonmetallic property of the elements reduces as we move from left to right in the period. As a result, F...
Answer: d) K > Mg > Al > B During a period, the metallic nature of the components diminishes as we move from left to right in the period. As a result, Mg > Al. With each group we...
Answer: (d) is a false statement When comparing orbitals with a lower value of 'n' to orbitals with a higher value of 'n,' it is easier to remove an electron from the lower value of 'n' orbital....
Answer: (a) Nuclear charge (Z) Because, in the case of isoelectronic species, the atomic size decreases as the number of nuclear charge increases (Z). e.g. the arrangement according to increasing...
Answer: Option c) Because the nucleus is made up of protons and neutrons, the mass of the nucleus has no effect on the valence shell. Protons, or nuclear charges, have an effect on the valence...
Answer: Correcting the incorrect statement is represented by option (b). It explains that "the d-block has 8 columns because a maximum of 8 electrons can occupy all of the orbitals in a d-subshell,"...
Answer: (c) The period in the Modern periodic table indicates the value of ‘n’ i.e. a principal quantum number. A periodic table's period reflects the value of a particular element's major quantum...
Answer: i) $Li_2O$ is formed when the alkali metal lithium (with one valence electron) and group 16 element oxygen (with two valence electrons) mix. (ii) The alkaline earth metal magnesium (which...
and the second 
ionization enthalpies (in 
) and the 
electron gain enthalpy (in ) of a few elements are given below: Which of the above elements is likely to be : (a) the least reactive element. (b) the most reactive metal. (c) the most reactive non-metal. (d) the least reactive non-metal. (e) the metal which can form a stable binary halide of the formula MX2 (X=halogen). (f) the metal which can form a predominantly stable covalent halide of the formula MX (X=halogen)?Elements (\Delta _{i}H_{1})(ΔiH1) (\Delta _{i}H_{2})(ΔiH2) (\Delta _{eg}H)(ΔegH) 1 520 7300 -60 2 419 3051 -48 3 1681 3374 -328 4 1008 1846 -295 5 2372 5251 +48 6 738 1451 -40 Answer:...
for 
(ii) (n1) 
for 
, and (iii) 
for 
, in the periodic table.Answer: i) Since n = 6, the element is in period 6. f-block element because the last electron enters f-orbital. They are in the third group. So, 54 + 7 + 2 + 1 Equals 64. So Gadolinium is required....
Answer: The general outer electronic configuration of s block elements is $ns ^{(1-2)}$. The general outer electronic configuration of p block elements is $ns ^{2} np ^{(1-6)}$. The general outer...
Answer: Group 1 elements have only one valence electron. So they tend to expel this electron to form a stable inert gas. The ionization enthalpies of the elements drop in group 1. Expulsion of the...
Answer: (a) The electrical configuration of an element with 5 electrons in the outer subshell is ns2np5. The electrical configuration of the Halogen group is the same. As a result, the elements...
Answer: Metals lose electrons to produce cations. Metals have low ionization, negative electron, and electronegativities enthalpies. ionic compounds and basic oxides Non-metals readily take...
Answer: The ionization enthalpy of any atom is determined by the number of protons and electrons in the atom. However, the isotopes of any element have the same number of electrons and protons as...
Answer: a) An atom loses one electron when it expels one, but the nuclear charge remains the same. In an atom, electron-electron repulsion reduces. So the effective nuclear charge increases. As a...
Answer: Electronegativity is a property of any element that is subject to change. Electronegativity varies depending on the substance being studied. The following statement is erroneous: "The...
Answer: Electron gain enthalpy Electronegativity It is the common tendency of an atom to attract outside electrons It is the general tendency of an atom to attract shared pair of electrons It is the...
Answer: Oxygen is in p block element group 16. It is the first of 16 members. It is a non-metal found in the earth's crust. When an electron is added to an O atom, it releases energy. O has a...
Answer: i) O and F are from the same period. As the electron is inserted in the same shell, the atomic size of O-atom is larger than F-atom. It has one less proton than F-atom. So an O-atom nucleus...
B Al Ga In Tl 801 577 579 558 589 Answer The ionization enthalpy decreases with group size. B and Al agree. Ga has a higher ionization enthalpy than Al. Tend electrons in the inner shell of...
Answer: The factors that cause the ionization enthalpy to drop as we travel down the main group are as follows: 1. “Inner shells increase in number as we proceed down the group.” The nucleus' inner...
Answer: Because magnesium has a larger 1st ionization enthalpy than sodium, Magnesium has bigger atoms than sodium. A higher effective nuclear charge than sodium, Magnesium So sodium requires less...
Answer: i) The electron that can be evacuated from Be(beryllium) atom is 2s, but the electron that can be expelled from boron is 2p. 2s – electron, and nucleus attract more strongly than 2s –...
. Calculate the ionization enthalpy of atomic hydrogen in terms of J mol–1.Answer: Given that, the electron of hydrogen is having $-2.18 * 10^{-18} J$ in the ground state. Thus, To eject an electron from the ground state in a $H ($ hydrogen $)-$ atom, a certain amount of...
Answer: In the ground state of an isolated gaseous atom, ionisation enthalpy is required to eject an electron. Even though the atoms are far separated in the gaseous state, there are some attraction...
Answer: It possesses less electrons than the parent atom, but the overall nuclear charge remains the same, resulting in greater attraction of electrons to the nucleus. Cations have smaller radii...
, and 
(a) What is common in them? (b) Arrange them in the order of increasing ionic radii.Answer: (a) All of the species have the same number of electrons, i.e. 10 electrons. They are, therefore, isoelectronic species. (b) The following is the arrangement of the given ions in ascending...
(ii) 
(iii) 
(iv) 
Answer: Isoelectronic species have the same number of electrons as one another. i) The elements $F^-$ and $O_2$ each have ten electrons. As a result, they are considered isoelectronic. (ii) The...
Answer: A period's left to right movement reduces atomic radius. Because external electrons are available in a comparable valence shell, the atomic number increases from left to right, increasing...
Answer: The atomic radius is the size of an atom. It measures an atom's size. If an element is a metal, its radius is metallic, and if it is not a metal, its radius is covalent. The metallic radius...
Answer: The number of valence electrons in any element determines the chemical and physical properties of that element. When elements in the same group of the periodic table have the same number of...
Answer: (i) Lawrencium (Lr), which has an atomic number of Z=103, and Berkelium (Bk), which has an atomic number of Z=97, are the two elements with the highest atomic numbers. (ii) Seaborgium (Sg),...
Answer: The first phase has two elements, while the second period has eight. As a result, element Z = 11 starts the third phase. The third period currently has eight elements. As a result, the 18th...
Answer: The seventh period of the periodic table contains elements with atomic numbers Z = 87–114. The element with Z = 114 is thus available in the seventh period. In the seventh period, the first...
Answer: For the outermost shells of a periodic table, a period shows the value of the main quantum number (n). Each period begins with the primary quantum number (n). And n for the 6th period is 6....
Answer: Mendeleev’s Approach for periodic law Modern approach for the periodic law Periodic functions of the atomic mass of the corresponding elements determine the chemical and physical properties...
Answer: Mendeleev arranged the elements in his periodic table by atomic weight. Mendeleev classified the elements into groups and periods based on atomic weight. Mendeleev grouped elements with...
Answer: It divides items into periods and groups based on their qualities. This method simplifies and organizes the study of elements and their compounds. Elements with similar characteristics are...
Option (iii) is the answer. The amount of energy released when an electron is added to an isolated gaseous atom is known as electron gain enthalpy. The electron gain enthalpy of F is less...
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![\[\left( \mathbf{ii} \right)\text{ }\left[ \mathbf{Xe} \right]\text{ }\mathbf{4}{{\mathbf{f}}^{\mathbf{7}}}~\mathbf{5d2}\text{ }\mathbf{6}{{\mathbf{s}}^{\mathbf{1}}}\]](https://www.learnatnoon.com/s/wp-content/ql-cache/quicklatex.com-0eea84eed0ff28f2a34c3dd7fdeaa933_l3.png "Rendered by QuickLaTeX.com")
![\[\left( \mathbf{iii} \right)\text{ }\left[ \mathbf{Xe} \right]\text{ }\mathbf{4}{{\mathbf{f}}^{\mathbf{7}}}~\mathbf{5}{{\mathbf{d}}^{\mathbf{1}}}~\mathbf{6}{{\mathbf{s}}^{\mathbf{2}}}\]](https://www.learnatnoon.com/s/wp-content/ql-cache/quicklatex.com-d9130ba366bc1be1b7d92e3b05d87326_l3.png "Rendered by QuickLaTeX.com")
![\[\left( \mathbf{iv} \right)\text{ }\left[ \mathbf{Xe} \right]\text{ }\mathbf{4}{{\mathbf{f}}^{\mathbf{8}}}~\mathbf{5}{{\mathbf{d}}^{\mathbf{6}}}~\mathbf{6}{{\mathbf{s}}^{\mathbf{2}}}\]](https://www.learnatnoon.com/s/wp-content/ql-cache/quicklatex.com-c4766769bfc3513e1f8e729a3f9c95cd_l3.png "Rendered by QuickLaTeX.com")
Option (iii) is the answer. The electronic configuration of gandolium is [Xe] 4f7 5d1 6s2