Answer:
The element argon is in column 8A and is a noble gas. Nobles gases are completely stable because their outershell is filled with all eight electrons. Argon has eight valence electrons.
<span>Chemists considered Martian
Periodic Table as one of the most useful tools they’ve used whose purpose is to
arrange the Martian elements according
to their properties and their atomic number. On this periodic table, it was
found out that the properties seem to vary.
Dmitri Mendeleev, the first to arrange the periodic table according to
atomic mass in a manner that the elements with the same properties were grouped
together. It was Henry Moseley who later arranged the periodic table in accord
to the increasing number of atoms per element. </span>
Answer:
Explanation:
The volume of the Sun is so huge that it could hold over 1 million Earths. The Sun is a typical star, and is also the star that is nearest to the Earth. It is composed of a mixture of 73% hydrogen, 25% helium, and 2% other elements by weight.
Answer:
cell :—
•They lack a well-defined nucleus, have a nucleoid instead.
•Usually have double-stranded, circular DNA.
•Do not have mitochondria.
Eukaryotic cell :—
•Have a well-defined nucleus enclosed in the nuclear membrane.
•Have a linear double-stranded nucleus.
•Mitochondria are present.
Answer:
It is a physical change because this change is reversible and no chemical reaction occurs.
Explanation: