A certain public water supply contains 0.10 ppb (part per billion) of chloroform `(CHCl_(3))`. How many molecules of `CHCl_(3)` would be obtained in 0.05 mL drop of this water?

A certain public water supply contains 0.10ppb (part per billion) of chloroform (CHCI_3) . How many molecules of CHCI_3 would be obtained in 0.478 mL drop of this water ?(assumed d=1g/mL )

What is the number of water molecules contained in a drop of water weighing 0.06g?

How many moles of electrons are required to Produce 10.0 g of Al from molten Al_2O_3 ?

The equilibrium constant for the following reaction in aqueous solution is 0.90. H_(3)BO_(3)+"glycerin"hArr(H_(3)BO_(3)-"glycerin") How many mole of glycerin should be added per litre of 0.10 M H_(3)BO_(3) so that 80% of the H_(3)BO_(3) is converted to the boric-acid glycerin complex ?

How many moles of of HCl are present in 250cm3 of 0.5 M HCl solution .

Three charges of +0.1 C each are placed at the vertices of an equilateral triangle of each side 1m. If the energy is supplied at the rate of 1.0 kw, how many hours would be required to move one of the charges on to the mid point of the line joining the other two? Given =1/(4piepsilon_0) = 9xx 10^9 N ^2C^-2

Radon is a radioactive gas with half-life 56 s.For health reasons,the maximum permissible level of radon in air in a building is set a t 1 radon atom for every .15xx10^(21) molecules of air 1 mol of air in the building is contained in 0.024 m^3 .Calculate ,for this building the number of molecules for air in 1.0 m^3 .

Radon is a radioactive gas with half-life 56 s.For health reasons,the maximum permissible level of radon in air in a building is set a t 1 radon atom for every .15xx10^(21) molecules of air 1 mol of air in the building is contained in 0.024 m^3 .Calculate ,for this building the maximum permissible number of radon atom in 1.0 m^3 of air

0.8 moles of a mixture of CO and CO_2 requires exactly 40 gram of NaOH in solution for complete conversion of all the CO_2 into Na_2 CO_3 . How many more of NaOH would for require for conversion into Na_2 CO_3 if the mixture (0.8 mole) is completely oxidised to CO_2 ?

A study was conducted to find out the concentration of sulphur dioxide in the air in parts per million (ppm) of a certain city. The data obtained for 30 days is as follows : For how many days, was the concentra-tion ofsulphur dioxide more than 0.11 parts per million.