Does it is a complete qwestion? It
is not clearef
Answer:
True
Explanation:
Dispensing chemical from large stock bottles into smaller container makes sure that students only takes the quantity they need which reduces wastage. Also in situation where the students did not finish the reagent or chemical it is easier for student to pour back into smaller bottle than the entire reagent bottle which can contaminate the whole solution. Small bottles prevent or reduces the risk of spillage because it is easier to handle and pour.
Answer: The number of series in Mendeleev's Periodic table is 12.
Explanation:
Horizontal rows present in the periodic table are called periods. Vertical rows in the periodic table are called series.
Mendeleev gave periodic table in the year 1869 by arranging elements according to their atomic weights a in tabular form.
Mendeleev's periodic table depicts 12 periods/series.
Thus, we can conclude that the number of periods/series in Mendeleev's Periodic table is 12.