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.
Answer:
As solute concentration increases, vapor pressure decreases.
Step-by-step explanation:
As solute concentration increases, the number of solute particles at the surface of the solution increases, so the number of <em>solvent </em>particles at the surface <em>decreases</em>.
Since there are fewer solvent particles available to evaporate from the surface, the vapour pressure decreases.
C. and D. are <em>wrong</em>. The vapour pressure depends <em>only</em> on the number of particles. It does not depend on the nature of the particles.
It is due to a lack of providable energy to the next trophic level of the energy pyramid. Primary consumers only obtain around 10% of energy that producers have, and the energy depletes as you move further and further up the food chain, until you reach the tertiary consumers which have the least amount of energy at their disposal, meaning there are less of them than other organisms further down the energy pyramid.
Hope this helped!
Answer:
A. star formation begins in a nebula.
Explanation:
A. The negative ionic radius is larger than the neutral atomic radius.
