IIT-JEE and NEET Chemistry problems

Learning from this problem: In this following problem you can learn about the application of ideal gas equation, mole concept, unit conversion, and determination of molecular weight. You can learn more different concepts from the similar types of practice problems. Problem1. 1.46 litre of a gas is collected over water at 30 C and 744 mm of Hg . If the gas weighs 1.98 g and vapour pressure of water at 30 C is 32 mm of Hg. What is the molecular weight of gas? Solution: Weight of the gas w = 1.98 g Volume of the gas V = 1.46 litre Pressure difference P = 744 – 32 = 712 mm of Hg = (712/760) atm Temperature of the gas T = (30 +273) K = 303 K Ideal gas follows following equation, PV = n RT ------------------- (1) Here, P = pressure , V = Volume, n= number of mole, R = Universal gas constant (0.0821) and T = Temperature Number of mole can be defined as follows, n =( Weight in g/ Molecular weight)= w/M If we substitute eve...

  Problem:1    A small piece of copper(Cu ) weighs 0.635 gm. How many atoms of copper(Cu) does it contain? Problem:2     The ethane gas molecule of weight around 5 gm are confined in cylinderical bulb of 1 litre capacity. These cylinderical bulb is so weak in nature, it will burst if the pressure exceeds more than 10 ATM. Calculate the bursting temperature of cylinder at which the pressure reach its maximum. Problem:3    A gas molecule occupies in the volume of 300 ml at the temperature of 27 C and 730 mm pressure. Calculate its volume at standard temperature and pressure. Problem:4    Estimate the weight in gm of 12.044 x 10 23 atoms of carbon. Problem:5     10 21 molecules of  CO2 removed from 200 mg of the same gas. How many moles of CO2 left in the gas cylinder? Problem:6     Estimate the number of sulphate ions in 100 ml of volume with the concentration of 0.001 M  sulphuric...