Answer:
Explanation:
Entropy is the degree of randomness or disorderliness of as system. The more random a system tends, the more positive the entropy. Gases have the highest entropy whereas solids have little to no entropy.
When a reaction goes from one initally with a lower entropy to one with a higher entropy, the change in entropy, ΔS is postive. ΔS is negative when a reaction goes from one with a higher entropy to one with lower entropy.
When there is no entropy change, both the reactants and products are in the same state.
In the first reaction, UF₆ is in a gaseous phase and it was seperated into two gaseous products, 238-UF₆ and 235-UF₆. Therefore, ΔS is zero i.e no change in entropy of the system.
In the second reaction, solid I₂ is dissolved in CCl₄. The solid substance goes into solution to form a liquid medium. This is an increase in the randomness or entropy of the system. Therefore ΔS is +ve.
Yes. density is a physical property that can be used to identify matter
Answer: For most of the life the chromosomes exists in a loose noodle like structure. They become compact to fit into a very small space.
Explanation: The chromosomes consists of a very long DNA that is linear. The liner DNA also has many proteins associated with it which is called as histone proteins.
These proteins fold and gets packed into a compact form from loose noodle or thread like structure.
This is necessary to get into a compact structure because being in linear form would require much space which is not possible. So as to manage the space and many processes like replication, repair and gene expression it is necessary for the chromosomes to get compact.