Chemical Bonding and Molecular Structure

High bond order => Short bond length Bond order = 3  

Same bond length means same bond order. Both CN^- and NO⁺ have bond order of 3. 

Greater the charge and smaller the radius, greater the polarising power and thus, greater the covalent nature. This leads to increase in lattice energy. 

Isoelectronic species have the same number of electrons. Al+3 has atomic number 13, so it has 13-3=10 electrons. F- has atomic number 9, so it has 9+1=10 electrons. Cl- has 18 electrons, Ar has 18 electrons, and S-- has 18 electrons - none match Al+3's 10 electrons.

Ammonium ferric citrate is a food additive used as an acidity regulator. It is a green or reddish-brown powder which is very soluble in water. The molecular formula of ammonium iron(III) citrate is variable. It can be prepared by adding Fe(OH)₂ to an aqueous solution of citric acid and ammonia.

Selenium hexasulphide is a chemical compound with formula Se₂S₆. Its molecular structure consists of a ring of two selenium and six sulphur atoms, analogous to the S₈ allotrope of sulphur (cyclooctasulphur) and other selenium sulphides with formula Se_nS_8-n.

Urea's chemical name is carbamide because it contains a carbonyl group (C=O) bonded to two amino groups (-NH2). Its formula is CO(NH2)2. Aneurin is vitamin B1, and chloroethane is an organic solvent - neither are related to urea.

Diehtylaminoethyl is the positively charged group of DEAE.

Intermolecular space influences intermolecular forces.

This compound does not exist.

This is correct.

Both CH₃Cl and NH₃ have C₃v point group.

SO₂Cl₂ has C2v point group.

This is correct.

RDX (Research Department Explosive) is a powerful high explosive used in military and commercial applications. DDT and BHC are both pesticides/insecticides, not explosives. RDX's chemical properties and classification as an explosive material are well-established in chemistry and military science, making it the correct answer.