I suppose you mean to ask why we can't go through obstacles.
Any atom is surrounded by an electronic cloud. When two atoms get close to each other, the electronic clouds repel each other, preventing them from interpenetrating each other. That same phenomenon, on a larger scale, prevents us from going through matter.
Answer:
1.B
2.A
3. B
Explanation:
1. A chemical bond is the physical phenomenon of chemical substances being held together by attraction of atoms to each other through sharing
2. so 2 is electrons of one atom are transferred permanently to another atom.meaning the answer is A
3. is When atoms combine by forming covalent bonds, the resulting collection of atoms is called a molecule. We can therefore say that a molecule is the simplest unit of a covalent compound.
1. solute is the substance that is being dissolve,while solvent is dissolving medium
2.saturated is solution that contain maximum amount of solut that capable of being dissolve and supersaturated is solution that contain less amount or medium of solut that capable being dissolve : example vinger
3. is a number placed in front of a chemical symbol or formula. It shows how many atoms or molecules of the substance are involved in the reaction. For example, two molecules of hydrogen would be written as 2 H2, and two molecules of water would be written 2 H2O . yes it's can be change only in caseWhen you balance an equation you can only change the coefficients
Answer: C
Explanation:
Some poly nuclear aromatic hydrocarbons are not carcinogenic in themselves. However, when these are made to interact with living cells, enzymes in the cells could convert the polynuclear aromatic hydrocarbon into a carcinogenic material such as benzo-[a]-pyrene. This can now interact adversely with the deoxyribonucleic acid of living cells leading to genetic mutation, that is, irreversible changes in the genes of organisms.
Answer:
Polymerization involves the synthesis of two or more monomers to get a polymer which is usually complex.
Polyvinyl alcohol can’t be used as a monomer(raw material) for polymerization because it is very unstable under normal conditions and will rearrange molecularly to give polyvinyl acetaldehyde.
