Advertisements
Advertisements
Question
If 0.2 mol of the following substance is required how many grams of that substance should be taken?
magnesium oxide
Advertisements
Solution
Molar mass of MgO = 24 + 16 = 40 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"/40 = 8`g
we need, 8g of MgO to obtain 0.2 moles of MgO.
APPEARS IN
RELATED QUESTIONS
What is the mass of 1 mole of nitrogen atoms?
What is the mass of 0.5 mole of water molecules?
One of the following elements has an atomicity of ‘one’. This element is :
Fill in the following blanks :
A mole represents an .............. number of particles of a substance.
Fill in the following blanks :
64 g of oxygen gas contains ................ moles of oxygen atoms.
How many moles are there in 34.5 g of sodium ? (Atomic mass of Na = 23 u)
How many moles are represented by 100 g of glucose, C6H12O6 ? (C = 12 u, H = 1 u, O = 16 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:
Avogadro’s number
What do you understand by the term mole? How many elementary units are in one mole of a substance?
Fill in the blank
One gram atom of an element contains ______ atoms.
Fill in the blank.
One a.m.u. is the mass of ______ atom of C12.
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?
If phosphorus is considered to contain P4 molecules, then calculate the number of moles in 100g of phosphorus?
Cost of Sugar (C12H22 O11) is Rs 40 per kg; calculate its cost per mole.
One mole of any gas occupies ______ ml at S.T.P.
Calculate the number of moles in 1.51 × 1023 molecules of NH4Cl.
How many grams are there in the following?
3 moles of chlorine molecule, Cl2.
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.
