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प्रश्न
What is the number of elements is 1st period the modern periodic table?
उत्तर
The number of elements in 1st period is 2 in the modern periodic table.
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संबंधित प्रश्न
Which of the following statement is correct in regard to the classification of elements?
(a) Elements in modern periodic table are arranged on the basis of increasing atomic masses.
(b) Elements in Mendeleev's periodic table are arranged on the basis of increasing atomic numbers.
(c) In modern periodic table, the element nickel of lower atomic mass is kept before the element cobalt of higher atomic mass.
(d) In modern periodic table, the isotopes of chlorine having different atomic masses are kept in the same group.
The atomic numbers of the three elements X, Y and Z are 2, 6 and 10 respectively.
(i) Which two elements belong to the same group?
(ii) Which two elements belong to the same period?
Give reasons for your choice.
Name two elements in each case:
Transition element
The electronic configuration of an element T is 2, 8, 8, 1.
What is the group number of T?
Give the symbol and valency of the following element and radical.
Sulphate
Give the chemical formula of sodium bicarbonate
State the number of elements in Period 2 of the Periodic Table.
Find the odd one out and give its explanation.
The modern periodic table is divided into which blocks?
- Write the electronic configuration of element X, given by its symbol as under: \[\ce{^40_20 X}\]
- Determine its position in the modem periodic table.
- What is the nature of its oxide?
- Name one other element of its group.
