Answer: 12 atoms
Explanation: the equation has 6H2 i.e
6*2 = 12
Answer:
(a) Eka-aluminum and gallium are two names of the same element as Eka-Aluminium has almost exactly the same properties as the actual properties of the gallium element. The properties: atomic mass, density, melting point, formula of chloride and formula of oxide are almost the same.
Explanation:
Scandium - Eka boron.
(ii) Gallium - Eka aluminium.
(iii) Germanium - Eka silicon.
Answer:
Dmitri Mendeleev
Explanation:
Dmitri Mendeleev a Russian Chemist arranged elements on the periodic table according to their atomic mass. He used this arrangement to predict some of the properties of the missing element.
- Dmitri Mendeleev around 1869 described the periodic table.
- The table was based on the periodic law which states that "chemical properties of elements are a periodic function of their atomic weights".
- In the Mendeleev table, elements are arranged by atomic weights with recurring properties in a periodic manner.