General
✓✗How many moles of lead (II) chloride will be formed from a reaction between 6.5 g of PbO and 3.2 g HCl?
- 0.011
- 0.029
- 0.044
- 0.333
General
✓✗Given the numbers : 161 cm, 0.161 cm, 0.0161 cm. The number of significant figures for the three numbers is
- 3, 3 and 4 respectively
- 3,4 and 4 respectively
- 3, 4 and 5 respectively
- 3, 3 and 3 respectively
General
✓✗What is the mass of the precipitate formed when 50 mL of 16.9% solution of AgNO3 is mixed with 50 mL of 5.8% NaCl solution? (Ag = 107.8, N = 14, O = 16, Na = 23, Cl = 35.5)
- 3.5 g
- 7 g
- 14 g
- 28 g
General
✓✗Volume of CO2 obtained by the complete decomposition of 9.85 g of BaCO3 is
- 2.24 L
- 1.12 L
- 0.84 L
- 0.56 L
General
✓✗Which has maximum molecules?
- 7 g N2
- 2 g H2
- 16 g NO2
- 16 g O2
General
✓✗An element, X has the following isotopic composition:
200X : 90% 199X : 8.0% 202X : 2.0%
The weighted average atomic mass of the naturally occurring element X is closest to
200X : 90% 199X : 8.0% 202X : 2.0%
The weighted average atomic mass of the naturally occurring element X is closest to
- 201 amu
- 202 amu
- 199 amu
- 200 amu
General
✓✗Specific volume of cylindrical virus particle is 6.02 ´ 10–2 cc/g whose radius and length are 7 Å and 10 Å respectively. If NA = 6.02 ´ 1023, find molecular weight of virus.
- 15.4 kg/mol
- 1.54 ´ 104 kg/mol
- 3.08 ´ 104 kg/mol
- 3.08 ´ 103 kg/mol
General
✓✗Boron has two stable isotopes, 10B(19%) and 11B(81%). Calculate average at. wt. of boron in the periodic table.
- 10.8
- 10.2
- 11.2
- 10.0
General
✓✗Suppose the elements X and Y combine to form two compounds XY2 and X3Y2. When 0.1 mole of XY2 weighs 10 g and 0.05 mole of X3Y2 weighs 9 g, the atomic weights of X and Y are
- 40, 30
- 60, 40
- 20, 30
- 30, 20
General
✓✗What is the weight of oxygen required for the complete combustion of 2.8 kg of ethylene?
- 2.8 kg
- 6.4 kg
- 9.6 kg
- 96 kg
General
✓✗An organic compound contains carbon, hydrogen and oxygen. Its elemental analysis gave C, 38.71% and H, 9.67%. The empirical formula of the compound would be
- CHO
- CH4O
- CH3O
- CH2O
General
✓✗What volume of oxygen gas (O2) measured at 0°C and 1 atm, is needed to burn completely 1 L of propane gas (C3H8) measured under the same conditions?
- 5 L
- 10 L
- 7 L
- 6 L
General
✓✗The number of water molecules is maximum in
- 1.8 gram of water
- 18 gram of water
- 18 moles of water
- 18 molecules of water.
General
✓✗The total number of valence electrons in 4.2 g of 
ion is (NA is the Avogadros number)
ion is (NA is the Avogadros number)- 2.1 NA
- 4.2 NA
- 1.6 NA
- 3.2 NA
General
✓✗A 5 molar solution of H2SO4 is diluted from 1 litre to a volume of 10 litres, the normality of the solution will be
- 1 N
- 0.1 N
- 5 N
- 0.5 N