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प्रश्न
On moving from left to right in a period in the periodic table, the size of the atom.
पर्याय
increases
decreases
does not change appreciably
first decreases and then increases
उत्तर
decreases
Explanation -
On moving from left to right in a period in the periodic table, the size of the atom decreases.
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संबंधित प्रश्न
On what basis elements are arranged in periodi table now?
On what basis did mandeleev arrange the elements in his periodic table?
(a) Write its electronic configuration and determine its valency.
(b) Is it more reactive or less reactive than Ca (atomic number 20)? Justify your answer giving reason.
(c) Is it a metal or a non-metal?
(d) Write the formula of its oxide.
Why did Mendel choose garden pea for his experiments? Write two reasons.
At the time of Mendeleev _______ elements were known.
While designing the periodic table, Mendeleev considered the chemical and physical properties of the elements.
An element has 12 protons. The group and period to which this element belongs is ______
According to Mendeléev's Periodic Law, the elements were arranged in the periodic table in the order of
In Mendeléev’s Periodic Table the elements were arranged in the increasing order of their atomic masses. However, cobalt with atomic mass of 58.93 amu was placed before nickel having an atomic mass of 58.71 amu. Give reason for the same.
Mendeléev predicted the existence of certain elements not known at that time and named two of them as Eka-silicon and Eka-aluminium.
- Name the elements which have taken the place of these elements
- Mention the group and the period of these elements in the Modern Periodic Table.
- Classify these elements as metals, non-metals or metalloids
- How many valence electrons are present in each one of them?
