Advertisements
Advertisements
Question
Deduce the number of molecules of the following compound in the given quantity.
90g water
Advertisements
Solution
Number of moles in water = `"Mass of water in grams"/"Molecular mass of water"`
= `90/18`
= 5 moles
∴ 5 moles of H2O contains = 5 × 6.022 × 1023 molecules = 30.11 × 1023 molecules.
The number of molecules in 90 grams of water is 3.01 × 1024.
APPEARS IN
RELATED QUESTIONS
What name is given to the amount of substance containing 6.022 × 1023 particles(atoms,molecules or ions) of a substance ?
Fill in the following blanks :
60 g of carbon element are .............. moles of carbon atoms.
What name is given to the amount of substance containing this number of atoms ?
Define mole. What are the two things that a mole represents.
How many moles of oxygen atoms are present in one mole of the following compounds ?
- Al2O3
- CO2
- Cl2O7
- H2SO4
- Al2(SO4)3
If 0.2 mol of the following substance is required how many grams of that substance should be taken?
Sodium chloride
The relative atomic mass of Cl atom is 35.5 a.m.u. Explain this statement.
Explain the term:
Gram atom
Given that the relative molecular mass of copper oxide is 80, what volume of ammonia (measured at STP) is required to completely reduce 120g of copper oxide? The equation for the reaction is :
3CuO + 2NH3 → 3Cu + 3H2O + N2
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?
The equation for the burning of octane is:
\[\ce{2C8H18 + 25O2 -> 16CO2 + 18H2O}\]
How many moles of carbon dioxide are produced when one mole of octane burns?
Correct the following statement :
Equal masses of all gases under identical conditions contain the same number of molecules.
Explain the term:
Molar volume
Calculate the mass of 0.1 mole of the following:
CaCO3
(Ca = 40, Na = 23, Mg = 24, S = 32, C = 12, Cl = 35.5, O = 16, H = 1)
Calculate the number of atoms in the following:
52 moles of He
Calculate the number of atoms in the following:
52 g 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?
Solid ammonium dichromate decomposes as:
\[\ce{(NH4)2Cr2O7 -> N2 + Cr2O3 + 4H2O}\]
If 63 g of ammonium dichromate decomposes. Calculate the quantity in moles of (NH4)2Cr2O7.
N2 + 3H2 → 2NH3
(The atomic mass of nitrogen is 14, and that of hydrogen is 1)
1 mole of nitrogen (______ g) +
3 moles of hydrogen (______ g) →
2 moles of ammonia (______ g)
Deduce the number of molecules of the following compound in the given quantity.
7.1 g chlorine
