Answer:
The correct answer will be option-D.
Explanation:
The semi-conservative mode of replication is the common method of replication used by mostly organisms on earth which were demonstrated by the Meselson and Stahl in 1958.
They used the isotopes of the nitrogen which contains extra neuron which makes the nitrogen-heavy and cultured them in bacteria
The experiment concluded that newly replicated double stranded DNA contains one newly synthesized DNA strand which is complementary to another parental strand. Thus new DNA molecule has one parental strand while other newly synthesized strand.
This is best illustrated by the option-D in the figure and therefore is the correct answer.
Answer:
the advantages of modern periodic tables are given below and explained.
- position of hydrogen:since hydrogen has the least atomic number i.e 1 ,it is kept in group 1 of modern periodic table, but still controversial due to its. dual characteristics since it shows the characteristics of borh group 1 and group 17.
- position of isotopes :isotopes are element having the same atomic number but different atomic weight . Without any doubt all isotopes of one element and kept in one place.
- position of lanthanide and acnitinides: element of Lanthanides series and element of Actinides series are kept below the main block of the periodic table as they have different properties from other elements.
- correction of periodic law: some elements do not obey mendeleev periodic law , but when they are arranged according to atomic number they obey the modern periodic law.
- position of alkali metals and coinage metals : in modern periodic table , alkali metal are kept in group IA and coinage metals are in group.
hope this helped you☺️
any confusion then comment it and let me know.
actually as I say these points say that the modern periodic table is better than mendeleev periodic table so, don't get confused.
Answer:
The group 15 elements: the pnicogens
Explanation:
The group 15 elements, nitrogen, phosphorus, arsenic, antimony and bismuth, all have the general valence shell electronic configuration ns2np3. They can all exist in the +3 or +5 oxidation state, with the +3 state increasing in stability as we move vertically down the group.
Answer:
Metal
Non-metal
Explanation:
CaF2 is an ionic compound. Ionic compounds are mostly composed of a metal and a non metal. Metals donate electrons to non-metals to form ionic compounds.
Calcium is a divalent ion of group two in the periodic table while F is a univalent nonmetal of group 17 in the periodic table. Hence the compound CaF2 is composed of a metal and a nonmetal.
The number of Zn particles (atoms of Zn ) in the first sample, and Zn ions are going to be the same,
Also mass of Zn are going to be the same, because of electrons are too small, and would not have influence on mass.
