Answer:
Prokaryotes are unicellular organisms that lack membrane-bound structures, the most noteworthy of which is the nucleus. ... While prokaryotic cells do not have membrane-bound structures, they do have distinct cellular regions. In prokaryotic cells, DNA bundles together in a region called the nucleoid.
The units of ppm means parts per million. Also, It is equivalent to milligrams per liter. It is one way of expressing concentration of a substance. It u<span>sually used to describe the concentration of something in water or soil. We calculate the mass of CaCO3 as follows:
Mass = 75 mg/L (.050 L) = <span>3.75 mg CaCO3</span></span>
The molecules or atoms that are formed by gain or loss of one or more valence electrons are said to be ions.
When atom loss one or more valence electrons, results in formation of cation whereas when atom gain one or more valence electrons, then formation of anion occurs. Cations carry positive charge and anions carry negative charge.
In general, cations are smaller than the neutral atoms from which they are formed and anions are larger than the neutral atoms.
As cations are smaller than the related neutral atoms because the valence electrons are lost which are farthest away from the nucleus. After that, taking more electrons distant from the cation results in reduction of radius of the ion.
Thus, aluminium cation consist of few electrons which results in fewer occupied energy levels by the electrons further results in reduction of radius i.e. smaller size.
Hence, given statement is true i.e. aluminium atom is larger than the aluminium cation as cation has fewer occupied energy levels.
Correct Answer: Option C i.e <span>Solution
Reason:
Solutions are characterized by particles of size less than 1nm. Since the particle size in solutions are very small, they cannot be separated by centrifugation. On other hand, colloids have particle size ranging from 1nm to 100 nm, while suspensions have particle size > 100 nm. Hence, they can be separated by centrifugation. </span>
