19,000+ solved questions for JEE Advanced, JEE Mains, NEET & IChO — with answers and expert explanations.
Who proposed Law of Conservation of Mass?
If 6.3g of NaHCO3 are added 15.0g CH3COOH solution, the residue is found to weigh 18.0 g. What is the mass of CO2 released in the reaction?
One of the statements of Dalton’s atomic theory in given below “Compounds are formed when atoms of different elements combine in a fixed ratio” Which of the following laws is not related to this…
_________is referred to as the closeness of different measurements for the same quantity.
How many significant figures are present in 0.10100 × 103?
Which of the following is the most accurate measurement?
The volume of 2 N H2SO4 solution is 0.1 dm3. The volume of its decinormal solution (in dm3) will be (MHT CET 2009)
The result of the operation 2.5 × 1.5 should be which of the following on the basis of significant figures?
2.005 has ….A…. significant figures. Here, A refers to
How can we write 232.508 in scientific notation?
Which of the following represents the largest unit?
Statement I: The temperatures in degree Celsius and degree Fahrenheit are related to each other by the following relationship. º F º C Statement II The temperature on degree Celsius and Kelvi…
Which of the following statements(s) is false about the arrangement of particles, in different states of matter?
A bivalent metal has an equivalent mass of 32. The molecular mass of the metal nitrate is (KCET 2009)
The number of molecules in 18 mg of water in terms of Avogadro number NA is (J&K CET 2009)
A metal M of equivalent mass E forms an oxide of molecular formula MxOy. The atomic mass of the metals is given by the correct equation (BCECE 2008)
The equivalent weight of a metal is 9 and vapour density of its chloride is 59.25. The atomic weight of metal is (DUMET 2008)
Of two oxides of iron, the first contained 22% and the second contained 30% of oxygen by weight. The ratio of weights of iron in the two oxides that combine with the same weight of oxygen is (J&K CET 2008)
How many moles of lead (II) chloride will be formed from a reaction between 6.5 g of PbO and 3.2 g of HCl? (CBSE AIPMT 2008)
Number of atoms of He in 100 u of He (atomic weight of He is 4) are (BCECE 2008)
The maximum number of molecules are present in (BCECE 2008)
Mass of 0.1 mole of methane is (KCET 2008)
If we consider that 1/6, in place of 1/12, mass of carbon atom is taken to be the relative atomic mass unit, the mass of one mole of a substance will
P and Q are two elements which forms P2Q3 and PQ2. If 0.15 mole of P2Q3 weights 15.9g and 0.15 mole of PQ2 weights 9.3g, the atomic weight of P and Q is (respectively) :
100 mL of mixture of NaOH and Na2SO4 is neutralised by 10 mL of 0.5 M H2SO4. Hence, NaOH in 100 mL solution is