Advertisements
Advertisements
प्रश्न
The modern periodic table has 1 to 7 periods.
पर्याय
Right
Wrong
उत्तर
The modern periodic table has 1 to 7 periods- Right
APPEARS IN
संबंधित प्रश्न
In the Modern Periodic Table, calcium (atomic number 20) is surrounded by elements with atomic numbers 12, 19, 21, and 38. Which of these have physical and chemical properties resembling calcium?
How does the metallic character of elements in Modern Periodic Table vary on moving from left to right in a period, and (ii) down a group?Give reason to justify your answer.
State modern periodic law.
Fill in the following blank with suitable word:
The basis for modern periodic table is ...............
Fill in the following blank with suitable word:
Group 1 elements are called ...............
What is the significance of atomic number in the modern classification of elements? Explain with the help of an example.
The three elements having chemical symbols of Si, B and Ge are:
(a) all metals
(b) all non-metals
(c) all metalloids
(d) Si is metalloid, B is metal and Ge is non-metal
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.
What is the number of valence electrons in the atoms of first elements in a period?
What is a period in a periodic table?
Explain why, the first period of the periodic table has only two elements whereas second period has eight elements
In what respects do the properties of group 1 elements differ from those of group 17 elements? Explain with examples by taking one element from each group.
Correct the statement.
Copper and zinc are representative elements.
Name two elements in Alkali metals.
Name two elements in Inert gas.
Name two elements in each case:
Actinides
Answer the following in respect of element `31/15 P`
Give its electronic configuration
Write a short note.
Position of isotopes in the Mendeleev’s and the modern periodic table.
State the modern periodic law.
How does number of (i) valence electrons (ii) valency; vary on moving from left to right in the second period of a periodic table?
In the Modern Periodic Table – atoms of all elements are arranged according to their increasing order of – atomic numbers. An atom of nitrogen has seven protons and seven electrons. State what would be its atomic number.
Give the symbol and valency of the following element and radical.
Potassium
Give the symbol and valency of the following element and radical.
Hydrogen
Give the symbol and valency of the following element and radical.
Aluminium
Give the symbol and valency of the following element and radical.
Hydroxide
Give the chemical formula of sodium sulphite
Give the chemical formula of carbonic acid
Mendeleev's periodic table : atomic mass : : Modern periodic table : _______
The K and L shells of the elements Na and Mg contain electrons.
In the modern periodic table, the positions of 1 to 20 elements are shown here. Identify the elements A and B. Write their atomic number.
Explain structure of modern periodic table in short.
Element ‘X’ forms a chloride with the formula XCl2, which is solid with a high melting point. X would most likely be in the same group of the periodic table as: ______
What is the symbol of the element Tungsten?
Which of the following is the outermost shell for elements of period 2?
Which one of the following elements exhibit maximum number of valence electrons?
Which of the following elements will form an acidic oxide?
Arrange the following elements in the increasing order of their metallic character
| Mg, | Ca, | K, | Ge, | Ga |
Choose an element from period 3 of modern periodic table that matches the description given below in instance. Give a reason for your choice.
It has same valency as Lithium.
An element ‘M' has 50% of the electrons filled in the 3rd shell as in the 2nd shell. The atomic number of ‘M’ is ______.
