The halogen elements have seven valence electrons in their outermost electron shell. Therefore, when these elements can receive an electron from another atom, they form very stable compounds since their outermost shell is full.

1 Answer. BRIAN M. Each Halogen ends in s2p5 with 7 valence electrons.

Hence, these elements consist of seven electrons in their outermost shell. Join BYJU’S to get your doubts clarified by our expert mentors….Aufbau principle.

The elements of Group 17 (fluorine, chlorine, bromine, iodine, and astatine) are called the halogens. The halogens all have the general electron configuration ns2np5, giving them seven valence electrons.

The group 17 elements include fluorine(F), chlorine(Cl), bromine(Br), iodine(I) and astatine(At) from the top to the bottom. They are called “halogens” because they give salts when they react with metals.

Complete step by step answer: The colour of halogens is due to the absorption of different quanta of radiations in the visible region which results in excitation of outer electrons to higher energy levels, thus different colours are observed. Halogens have unpaired electrons in their outermost shell.

The colour of a molecule does not depend on the whether the molecule is diamagnetic or paramagnetic. The reason is that the colour is caused by absorption of a photon in the visible part of the spectrum.

Whenever light falls on the transition element compounds electrons excite and electrons absorb energy and excite. When these electrons de-excite they release visible light wavelength. That’s why transition element compounds exhibit colour.

Interhalogen are all prone to hydrolysis and ionize to give rise to polyatomic ions. The inter halogens are generally more reactive than halogens except F. This is because A-X bonds in interhalogens are weaker than the X-X bonds in dihalogen molecules.

Why? Ans. Cu2+ (3d 9 4s 0) has one unpaired electron in d-subshell which absorbs radiation in visible region resulting in d-d transition and hence Cu2+ salts are coloured. No radiation is absorbed for d- d transition and hence Zn2+ salts are colourless.

Although there is splitting, but because of the d10 configuration, there is no vacancy in the higher energy d orbital for the promotion to take place. Since no colour is absorbed, the white light passes through and hence the solution appears colourless.

Zn2+ salts are white while Cu2+ salts are coloured. Zn2+ has completely filled d-orbitals (3d10), while Cu2+ has incompletely filled d-orbitals (3d9); therefore, d-d transition is possible in Cu2+, which imparts colour to copper (II) salts. 11828 Views. 8.

Zn2+(3d10) salts have no impaired electrons but Cu2-(3d9) salts have one unpaired electrons. Hence Zn2+ salts are white while Cu2- salts are coloured.

the colour of transition elements is due to the presence of unpaired electrons. cu+ is colourless as its outermost configuration is 3d10 …so there are no unpaired electrons which causes the colour .

Zinc chloride is the name of chemical compounds with the formula ZnCl2 and its hydrates. Zinc chlorides, of which nine crystalline forms are known, are colorless or white, and are highly soluble in water. This white salt is hygroscopic and even deliquescent.

The d-And-f-Block Elements. Why Zn2+ salts are white while Ni2+ salts are blue? Zn2+ has completely filled d-orbitals (3d10) while Ni2+ has incompletely filled d-orbitals (3d8). thus d-d transition take place and nickel show blue color.

Toxicity Zinc chloride is corrosive by ingestion and highly irritant by inhalation. Features Topical – Topical zinc chloride causes ulceration and burns and chronic exposure has been associated with anorexia, fatigue and weight loss.

All Answers (8) Zinc chloride is very soluble in water & will usually form clear solution. With excess water, zinc oxychlorides are formed. ZnCl2 also dissolves in ethanol & also in acetone.

ZnCl2 is a Lewis acid because it can accept an electron pair from a Lewis base. A Lewis acid is a molecule that can accept an electron pair and a Lewis base is a molecule that can donate and electron pair. Thus, ZnCl₂ will behave as a Lewis acid in an attempt to acquire more valence electrons.

Zinc Chloride is an ionic salt essential for the synthesis of cholesterol, protein, and fats.

Dissociation of magnesium hydroxide Mg(OH)2(s) → Mg2+(aq) + 2OH–(aq) c.

A dissociation reaction is a chemical reaction in which a compound breaks apart into two or more components. The general formula for a dissociation reaction follows the form: AB → A + B.

At a pH of 7–8.5, MgO can dissociate in an overall reaction of MgO + H2O → Mg2+ + 2OH− (Fruhwirth et al. 1985); the dissociation rate in this case is dependent upon OH− adsorption and subsequent Mg2+ and OH− desorption.

According to the obtained results, chemical dissolution of MgO/ MgSiO 4 in acidic solutions leads to the increased local pH, which facilitates precipitation of insoluble precipitate cerium oxide/hydroxide compound [122] [123][124].