Advertisements
Advertisements
प्रश्न
The relative atomic mass of Cl atom is 35.5 a.m.u. Explain this statement.
Advertisements
उत्तर
The relative atomic mass of Cl atom is 35.5 a.m.u. because chlorine consists of a mixture of two isotopes of masses 35 and 37 in the ratio of 3 : 1.
The average of the isotopic masses is 35 x 3 + 37 x 4 = 35.5
Concept Insight: Isotopes are atoms of same having same atomic number but different mass number.
APPEARS IN
संबंधित प्रश्न
Calculate the number of moles in 12g of oxygen gas.
How many moles of calcium carbonate (CaCO3) are present in 10 g of the substance ? (Ca = 40 u ; C = 12 u ; O = 16 u)
How many moles are there in 34.5 g of sodium ? (Atomic mass of Na = 23 u)
What weight of each element is present in 1.5 moles of sodium sulphite, Na2SO3 ?
(Atomic masses : Na = 23 u ; S = 32 u ; O = 16 u)
Define the term Relative atomic mass.
A gas cylinder can hold 1 kg of hydrogen at room temperature and pressure.
(a) Find the number of moles of hydrogen present
(b) What weight of CO2can the cylinder hold under similar conditions of temperature and pressure? (H = 1 C = 12, O = 16)
(c) If the number of molecules of hydrogen in the cylinder is X, calculate the number of CO2 molecules in the cylinder with the same conditions of temperature and pressure.
(d) State the law that helped you to arrive at the above result.
Calculate the number of atoms in the following:
52 moles of He
The molecular formula for elemental sulphur is S8. In a sample of 5.12 g of sulphur:
How many moles of sulphur are present?
One mole of any gas occupies ______ ml at S.T.P.
Fill in the missing data in the Table
| Species Property | H2O | CO2 | Na atom | MgCl2 |
| No. of moles | 2 | - | - | 0.5 |
| No. of particles | - | 3.011×1023 | - | - |
| Mass | 36g | - | 115 g | - |
