Advertisements
Advertisements
प्रश्न
If 0.2 mol of the following substance is required how many grams of that substance should be taken?
Calcium carbonate
Advertisements
उत्तर
Molar mass of CaCO3 = 40 + 12 + 3(16) = 100 g/mol
Number of moles of a substance = `"Mass of the substance in grams"/"Molecular mass of the substance"`
Let Mass of the substance in grams be x,
`0.2 = "x"/100 = 20`g
we need, 20 g of CaCO3 for obtaining 0.2 moles of CaCO3.
APPEARS IN
संबंधित प्रश्न
What is the mass of 4 moles of aluminium atoms (Atomic mass of aluminium = 27)?
If the aluminium salt of an anion X is Al2X3, what is the valency of X ? What will be the formula of the magnesium salt of X ?
Fill in the following blanks :
64 g of oxygen gas contains ................ moles of oxygen atoms.
How many moles of calcium carbonate (CaCO3) are present in 10 g of the substance ? (Ca = 40 u ; C = 12 u ; O = 16 u)
What is meant by ‘a mole of carbon atoms’ ?
Explain with examples what is meant by a 'mole' of a substance.
The relative atomic mass of Cl atom is 35.5 a.m.u. Explain this statement.
Define the term.
Molar volume
A flask contains 3.2g of sulphur dioxide.Calculate the following : The moles of sulphur dioxide present in the flask.
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 volume of dinitrogen oxide is produced at the same time as 8.96 L of steam?
Correct the following statement :
Equal masses of all gases under identical conditions contain the same number of molecules.
Which of the following would weight the least?
[Atomic masses : Ag = 108, N - 14, O = 16,C = 12]
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 mass of 0.1 mole of the following:
Mg
(Ca = 40, Na = 23, Mg = 24, S = 32, C = 12, Cl = 35.5, O = 16, H = 1)
The molecular formula for elemental sulphur is S8.In a sample of 5.12 g of sulphur:
How many molecules and atoms are present?
Which of the following weighs the least?
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 | - |
Deduce the number of molecules of the following compound in the given quantity.
8.8g carbon dioxide
