Answer:
Scandium
Explanation:
Mendeleev played an important role in the development of the modern periodic table. His periodic table was filled with gaps. He said that these gaps were elements that were yet to be discovered. He rightly predicted many elements which have now been discovered and fitted in their proper places in the periodic table.
He used the prefix ''eka'' to refer to elements whose properties were alike but were yet to be discovered at that time.
The compound named ekaboron which he predicted to have an atomic weight between 65 (zinc) and 75 (arsenic) with a valence similar to aluminum was later discovered in 1879 and properly named scandium.
Barium is an element that is primarily used in fireworks because of its distinct green colour while on the other hand, lead is used in electrical industries due to its unique properties. The ions of these elements can simply be identified when its insoluble salts get precipitated by any process.
Answer:
HCl
Explanation:
The best solvent for NaF is a polar liquid. The only liquid having a significant dipole moment among the options is HCl due to the large electro negativity difference between hydrogen and chlorine.
The polar solvent can interact with the NaF via its dipoles such that the NaF dissolves due to ion-dipole interaction.
<span>There are more than 550 active
volcanoes in the world, almost all of which are located at convergent
tectonic plate boundaries. This includes all of the volcanoes in the
Pacific Ring of Fire, such as Japan's Mount Fuji, as well as Mount Saint
Helens, Popocafepetl in Mexico and Azul in the Andes Range.</span>
Answer:
it's urine option ( C ) .
