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.
The closeness of a measurement to its true value is a measure of its accuracy. This term is the degree of which a certain measurement conforms to the correct value or the standard value. It is not the same with the term precision. Precision, on the other hand, is a measure used to characterize the closeness of the data measured.
Answer:
A
Explanation:
Quaternary structure of proteins is composed of two or more polypeptide chains. Insulin has two; one alpha and one beta chain. The two chains are joined together by disulfide bonds at two points (at cysteines). Other examples of quaternary proteins structures are DNA polymerase and hemoglobin.
The semifluid or hot fluid substance within or below the crust of the Earth from which lava and other igneous rock are produced by cooling is known as magma.
The temperature and pressure elevate with depth, finally reaching to a level wherein the strongest rock is melted, transforming into magma. When the magma comes into contact with water, it instantly gets transformed into a rock, that is, the outside solidifies briskly, and the inside of it gets cold.
