How many grams of concentrated nitric acid solution should be used to prepare 250 mL of 2.0 M HNO3? The concentrated acid is 70% HNO3.
(a) 45.0 g conc. HNO3
(b) 90.0 g conc. HNO3
(c) 70.0 g conc. HNO3
(d) 54.0 g conc. HNO3
Difficulty Level:
Mole fraction of the solute in a 1.00 molal aqueous solution is
(a) 0.0177
(b) 0.0344
(c) 1.7700
(d) 0.1770
Difficulty Level:
6.02x1020 molecules of urea are present in 100mL of its solution. The concentration of solution is
(a) 0.02M
(b) 0.01M
(c) 0.001M
(d) 0.1M
Difficulty Level:
Difficulty Level:
The number of moles of KMnO4 reduced by one mole of KI in alkaline medium is
(a) one fifth
(b) five
(c) one
(d) two
Difficulty Level:
The number of moles of oxygen in 1L of air containing 21% oxygen by volume, under standard conditions, is
(a) 0.0093 mole
(b) 2.10 moles
(c) 0.186 mole
(d) 0.21 mole
Difficulty Level:
What volume of oxygen gas (O2) measured at and 1 atm, is needed to burn completely 1L of propane gas (C3H8) measured under the same conditions?
(a) 7L
(b) 6L
(c) 5L
(d) 10L
Difficulty Level:
1 g of magnesium is burnt with 0.56g of oxygen in a closed vessel. Which reactant is left in excess and how much?
(At. weight of Mg = 24, O=16)
(a) Mg, 0.16g
(b) O2, 0.16g
(c) Mg, 0.44g
(d) O2, 0.28g
Difficulty Level:
Percentage of Se in peroxidase anhydrase enzyme is 0.5% by weight (at. weight = 78.4), then minimum molecular weight of peroxidase anhydrase enzyme is
(a) 1.568 x 103
(b) 15.68
(c) 2.168 x 104
(d) 1.568 x 104
Difficulty Level:
Number of moles of Mn required to oxidise one mole of ferrous oxalate completely in acidic medium will be
(a) 0.6 mole
(b) 0.4 mole
(c) 7.5 moles
(d) 0.2 mole
Difficulty Level: