Advertisements
Advertisements
प्रश्न
What name is given to the number 6.022 × 1023 ?
उत्तर
The name given to the number 6.022 × 1023 is Avogadro’s number.
APPEARS IN
संबंधित प्रश्न
An element has an atomic number of 11 and its mass number is 23. What is the arrangement of electrons in the shells? State nuclear composition of an atom of the element.
The atomic number of an element E is 16. The number of electrons in its ion E2– will be :
The number of electrons in an ion Y2+ is 10. The atomic number of element Y is most likely to be :
The atom of an element X contains 17 protons, 17 electrons and 18 neutrons whereas the atom of an element Y contains 11 protons, 11 electrons and 12 neutrons.
- What type of ion will be formed by an atom of element X ? Write the symbol of ion formed.
- What will be the number of (i) protons (ii) electrons, and (iii) neutrons, in the ion formed from X ?
- What type of ion will be formed by an atom of element Y ? Write the symbol of ion formed.
- What will be the number of (i) protons (ii) electrons, and (iii) neutrons, in the ion formed from Y ?
- What is the atomic mass of (i) X, and (ii) Y ?
- What could the elements X and Y be ?
What is the numerical value of Avogadro number ?
What name is given to this number ?
What is the number of molecules in 1.5 moles of ammonia ?
Which of the following has the maximum number of atoms ?
If one gram of sulphur contains x atoms, calculate the number of atoms in one gram of oxygen element.
(Atomic masses : S = 32 u ; O = 16 u)
How many grams of magnesium will have the same number of atoms as 6 grams of carbon ?
(Mg = 24 u ; C = 12 u )
The mass of one atom of an element X is 2.0 × 10–23 g.
Calculate the atomic mass of element X.
What could element X be ?
A gold sample contains 90% of gold and the rest copper. How many atoms of gold are present in one gram of this sample of gold?
A silver ornament of mass ‘m’ gram is polished with gold equivalent to 1% of the mass of silver. Compute the ratio of the number of atoms of gold and silver in the ornament.
Match the names of the Scientists given in column A with their contributions towards the understanding of the atomic structure as given in column B
(A) | (B) | ||
(a) | Ernest Rutherford | (i) | Indivisibility of atoms |
(b) | J.J.Thomson | (ii) | Stationary orbits |
(c) | Dalton | (iii) | Concept of nucleus |
(d) | Neils Bohr | (iv) | Discovery of electrons |
(e) | James Chadwick | (v) | Atomic number |
(f) | E. Goldstein | (vi) | Neutron |
(g) | Mosley | (vii) | Canal rays |
The atomic number of calcium and argon are 20 and 18 respectively, but the mass number of both these elements is 40. What is the name given to such a pair of elements?
Helium atom has 2 electrons in its valence shell but its valency is not 2, Explain