Advertisements
Advertisements
Question
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)
Advertisements
Solution
1.5 moles of sodium sulphite
Molar mass of sodium sulphite = (2 × 23) + (1 × 32) + (3 × 16) = 126g
Therefore, 1 mole of sodium sulphite weighs 126g.
Now, 1 mole of sodium sulphite contains 2 moles of sodium.
So, mass of sodium in 1 mole of sodium sulphite = 2 × 23 = 46g
Therefore, mass of sodium in 1.5 moles of sodium sulphite is = 1.5 × 46 = 69g
1 mole of sodium sulphite contains 1 mole of sulphur.
So, mass of sulphur in 1 mole of sodium sulphite = 1 × 32 = 32g
Therefore, mass of sulphur in 1.5 moles of sodium sulphite is = 1.5 × 32 = 48g
1 mole of sodium sulphite contains 3 moles of oxygen.
So, mass of oxygen in 1 mole of sodium sulphite = 3 × 16 = 48g
Therefore, mass of oxygen in 1.5 moles of sodium sulphite is = 1.5 × 48 = 72g
Hence, the mass of sodium, sulphur and oxygen in sodium sulphite is 69g, 48g and 72g, respectively.
APPEARS IN
RELATED QUESTIONS
Convert into mole.
22 g of carbon dioxide
One of the following elements has an atomicity of ‘one’. This element is :
What is a group of 6.022 × 1023 particles known as ?
How many moles are represented by 100 g of glucose, C6H12O6 ? (C = 12 u, H = 1 u, O = 16 u)
What is meant by ‘a mole of carbon atoms’ ?
If 0.2 mol of the following substance is required how many grams of that substance should be taken?
Sodium chloride
What do you understand by the term mole? How many elementary units are in one mole of a substance?
Calculate the number of moles of CO2 which contain 8.00 g of O2
What mass of Ca will contain the same number of atoms as are present in 3.2 g of S?
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 | - |
