Advertisements
Advertisements
Question
The difference in the mass of 100 moles each of sodium atoms and sodium ions is 5.48002 g. Compute the mass of an electron.
Advertisements
Solution
Number of electrons in Na atom = 11
Number of electrons in Na+ = 10
For 1 mole of Na atom and Na+ the difference in electrons = 1 mole
For 100 moles of Na atoms and Na ions the
difference = 100 moles of electrons
Mass of 100 moles of electrons = 0.0548002 g
Mass of 1 moles of electron = `0.0548002/100"g"`
Mass f 1 electron = `0.0548002/(100 xx 6.022 xx 10^23)`
= 9.1 × 10−28 g
= 9.1 × 10−31 g
APPEARS IN
RELATED QUESTIONS
One of the following elements has an atomicity of ‘one’. This element is :
Calculate the mass in grams of 0.17 mole of hydrogen sulphide, H2S. (Atomic masses : H = 1 u, S = 32 u)
Define the term Relative atomic mass.
Explain the term:
Gram atom
A sample of ammonium nitrate when heated yields 8.96 litres of steam (measured at STP)
NH4NO3 → N2O + 2H2O
What mass of ammonium nitrate should be heated to produce 8.96L of steam?
Define the term:
Relative molecular mass
Calculate the mass of 0.1 mole of the following:
CaCl2
(Ca = 40, Na=23, Mg =24, S=32, C = 12, Cl = 35.5, O=16, H=1)
Match the following.
| 1. | 8 g of O2 | - | 4 moles |
| 2. | 4 g of H2 | - | 0.25 moles |
| 3. | 52 g of He | - | 2 moles |
| 4. | 112 g of N2 | - | 0.5 moles |
| 5. | 35.5 g of Cl2 | - | 13 moles |
Compute the difference in masses of 103 moles each of magnesium atoms and magnesium ions.
(Mass of an electron = 9.1×10–31 kg)
Deduce the number of molecules of the following compound in the given quantity.
8.8g carbon dioxide
