250mL of a sodium carbonate solution contains 2.65 grams of Na2CO3. If 10mL of this solution is diluted to one litre, what is the concentration of the resultant solution?
(mol. wt. of Na2CO3= 106)
Molarity of given Na2CO3 sol.
or M2 = 0.001 M
One mole of calcium phosphide on reaction with excess of water gives
Number of g of oxygen in 32.2 g Na2SO4. 10H2O is
The percentage of Se in peroxidase anhydrous enzyme is 0.5% by weight (atomic weight = 78.4). Then minimum molecular weight of peroxidaseanhydrous enzyme is
The percentage of nitrogen in urea is about
How much of NaOH is required to neutralize 1500 cm3 of 0.1 N HCl? (Na = 23)
10 dm3 of N2 gas and 10 dm3 of gas X at the same temperature contain the same number of molecules. The gas X is
The volume of water to be added to 100 cm3 of 0.5 N H2SO4 to get decinormal concentration is
7.5 grams of a gas occupy 5.6 litre of volume at S.T.P The gas is
An aqueous solution of 6.3 g of oxalic acid dihydrate is made up to 250mL. The volume of 0.1 N NaOH required to completely neutralize 10mL of this solution is
How many moles of electrons weight one kilogram?