Advertisements
Advertisements
प्रश्न
Compute the difference in masses of one mole each of aluminium atoms and one mole of its ions. (Mass of an electron is 9.1×10–28 g). Which one is heavier?
Advertisements
उत्तर
Mass of 1 mole of aluminium atom = 27g mol−1
Al − 3e− → Al3+ (3 moles of electrons)
Mass of 3 moles of electrons
= 3 × (9.1 × 10−28) × 6.022 × 1023 g
= 0.00164g
Molar mass of Al3+ = 27 − 0.00164g mol−1
= 26.9984g mol−1
Difference = 27 – 26.9984
= 0.0016 g
1 mole of Al atoms is heavier than 1 mole of Al3+ions.
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.
If the number of electrons in an ion Z3– is 10, the atomic number of element Z will be :
The atomic number of an element E is 16. The number of electrons in its ion E2– will 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 ?
If 32 g of sulphur has x atoms, then the number of atoms in 32 g of oxygen will be :
If 12 gram of carbon has x atoms, then the number of atoms in 12 grams of magnesium will be :
What mass of nitrogen, N2, will contain the same number of molecules as 1.8 g of water, H2O ?
(Atomic masses : N = 14 u ; H = 1 u ; O = 16 u)
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)
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 ?
Classify each of the following on the basis of their atomicity.
- F2
- NO2
- N2O
- C2H6
- P4
- H2O2
- P4O10
- O3
- HCl
- CH4
- He
- Ag
Which has more number of atoms?
100g of N2 or 100 g of NH3
. A sample of ethane (C2H6) gas has the same mass as 1.5 ×1020 molecules of methane (CH4). How many C2H6 molecules does the sample of gas contain?
In the atom of an element X, 6 electrons are present in the outermost shell. If it acquires noble gas configuration by accepting requisite number of electrons, then what would be the charge on the ion so formed?
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 |
Helium atom has 2 electrons in its valence shell but its valency is not 2, Explain
