1. While making sulphuric acid solutions, acid must added slowly in in water under stirring. 2. Water should be cold.

The bond formed by the transfer of electron(s) from an electropositive element to an electronegative element is called an ionic bond or electrovalent bond. For instance, in salt (Sodium chloride) we see, sodium (Na) becomes Na+ by donating an electron to chlorine, which in turn becomes Cl-. Then Na+ and Cl- combine together to form NaCl (Sodium chloride).

The bond formed by the sharing of valence electrons between two or more elements or atoms of the same element is called a covalent bond. This feature is usually prevalent in non-metals. For instance, in a hydrogen molecule (H2), we see each hydrogen atom has one valence electron. Now, the electrons of the two atoms of hydrogen combine together to form one molecule of hydrogen (H2).

Two or more miscible liquids having different boling points can be separated by fractional distillation method. T

But mass of 1 mole of CH4 is 16 g while that of CO2 is 44 g, so 44 g of CO2 will be formed by combustion of 16g of CH4.

Total 3 isomers are possible.

10.4 G OF BUTANE

The basicity of amines is a Lewis basic character that is the electron-donating capacity of nitrogen in the above structures. Now Pyrrole (A), Pyridine ((B), and Aniline (D) structures are aromatic compounds obeying Huckel's rule and delocalization of pi electrons. In all of these  Lone pair of electrons of nitrogen is delocalized with pi electron cloud of the aromatic ring. But in hexa-hydro pyridine  (B) the Lone pairs are on nitrogen and can be donated 

Thus B is most basic out of all

Some of the example are Alcohol and water Air mixture Petroleum mixture

By reading the question, it is being asked that halogen atom hybridisation in haloalkane. It is the halogen atom which is attached to sp3 hybridised carbon atom in the haloalkane through a single bond. Halogen atom itself is not hybridised.