Which of the following reactions are exothermic?

 

$$\begin{gathered} 1) C + O2 → CO2 \\ 2) 2Mg + O2 → 2MgO \\ 3) CuSO4 + 5H2O → CuSO4.5H2O \\ 4) All the above \end{gathered}$$

The P atom needs five orbitals to form the five P-Cl bonds. It has a 3s and three 3p orbitals, so it must use one of its 3d orbitals to form the fifth bond. These orbitals are hybridized to form five sp3d orbitals that just happen to point in the right directions to form a trigonal bipyramid.

Lysosome is found in nearly all types of eukaryotic cells (cells with a clearly defined nucleus) and is responsible for the digestion of macromolecules, old cell parts, and microorganisms. Each lysosome is surrounded by a membrane that maintains an acidic environment within the interior via a proton pump. Lysosomes contain a wide variety of hydrolytic enzymes (acid hydrolases) that break down macromolecules such as nucleic acids, proteins, and polysaccharides. So, they are known as storehouse of digestive enzymes.

Nylon is made when the appropriate monomers (the chemical building blocks which make up polymers) are combined to form a long chain via a condensation polymerisation reaction. The monomers for nylon 6-6 are adipic acid and hexamethylene diamine

Fischer projections were originally proposed for the depiction of carbohydrates and used by chemists, particularly in organic chemistry and biochemistry.A Fischer projection always uses an eclipsed conformation. A Newman diagram can represent either an eclipsed conformation or a staggered conformation or a skew conformation.

The haloalkanes (also known as halogenoalkanes or alkyl halides) are a group of chemical compounds derived from alkanes containing one or more halogens.Halogens can’t form more than one bond in the context of common organic compounds and can’t form multiple bonds to carbon.