Based on the periodic table, the element mendeleev called eka-manganese is now called technetium. Technetium<span> is a silvery-gray metal that tarnishes slowly in moist air. Hope this answers the question. Have a nice day. Feel free to ask more questions.</span>
The answer is B
I also did this quiz.
The number of valence electrons of an element can be determined by the periodic table group (vertical column) in which the element is categorized
Answer:
Which sequence of events is required to form a limestone cave where you can walk around and observe cave formations, such as stalactites? (Note: stalactites hang from the ceiling - they have to hold on tight to the roof.)
A geological sequence of events as involving the lowering of the water table to expose cave structures where stalactites and stalagmites form which is described as follows,
Explanation:
1. Acidic percolated water formed cavities of solution beneath the natural water table known as phreatic zone
2. After the passage of time there is a drop in the water table dropped forming caves from cavities
3. These caves, which are air filled voids that contains adequate environment for forming stalactites and stalagmites and where they are found
