19,000+ solved questions for JEE Advanced, JEE Mains, NEET & IChO — with answers and expert explanations.
If 1 12 moles of oxygen combine with Al to form Al2O3, the weight of Al used in the reaction is (Al = 27)
Which of the following contains atoms equal to those in 12 g Mg ? (At. wt. Mg = 24)
Which of the following represents 180 g of water correctly? (I) 5 moles of water. (II) 10 moles of water. (III) 6.023 × 1023 molecules of water. (IV) 6.023 × 1024 molecules of water. Choose the correct option.
The mass of 112 cm3 of CH4 gas at STP is
The number of molecules in 89.6 litre of a gas at NTP are :
Number of molecules in 1 litre of oxygen at STP is : (a) 6.02×10 (b) 6.02×10 22.4
M g of a substance when vaporised occupy a volume of 5.6 litre at NTP. The molecular mass of the substance will be :
How many significant figures does 63180 have?
_________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 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…
…A… are formed when atoms of different elements combine in a …B… ratio. Here, A and B refer to
O Thus, 1.0 g Mg reactis with 0.67 . g O But only 0.56g O is available which less than 0.67 g is. Thus, O . is the limiting reagent. MOLE & EQUIVALENT CONCEPT Further, 16g O reacts with 24g of Mg. 0.56g O will re…
1.0 g of magnesium is burnt with 0.56 g O2 in a closed vessel. Which reactant is left in excess and how much? (At. wt. Mg = 24, O = 16) (NEET 2014)
When 22.4 litres of H2(g) is mixed with 11.2 litres of Cl2(g), each at STP, the moles of HCl(g) formed is equal to (NEET 2014)
Equal masses of H2, O2 and methane have been taken in a container of volume V at temperature 27°C in identical conditions. The ratio of the volumes of gases H2 : O2 : methane would be (NEET 2014)
6.02 × 1020 molecules of urea are present in 100 mL of its solution. The concentration of solution is (NEET 2013)
The vapour density of a gas is 11.2. The volume occupied by one gram of the gas at STP is (Manipal – 2013)
20.0 kg of N2(g) and 3.0 kg of H2(g) are mixed to produce NH3 (g). The amount of NH3(g) formed is (Kerala CEE 2011)
60g of a compound on analysis produced 24g of carbon, 4g hydrogen and 32g oxygen. The empirical formula of the compound is. (BVP 2010)