Small quantities of hydrogen can be prepared by the addition of hydrochloric acid to zinc. a sample of 195 ml of hydrogen was collected over water at 25°c and 753 torr. what mass of hydrogen was collected? (pwater = 24 torr at 25°c)

mass of hydrogen collected is 0.016 gram

Explanation:

Given values:

For calculating mass we have to find the number of moles first  

Ideal gas equation   PV =nRT

Volume= 195 ml

Pressure: 753 torr =0.99 atm

Temperature: 25+273= 298 Kelvin

Ideal gas constant R= 0.0821 Latm/molK

Number of moles n= ?

So n=  PV/RT

Adding the values  

n= = (753 torr)(1 atm/760 torr)(195 mL)(1 L/1000 mL)/(0.0821 L·atm/mol·K)(273 K)

n = 0.007897 moles of H₂

Now mass of hydrogen collected = number of moles x Molar mass of H₂

                                                     = 0.007897 x 2  

                                                        = 0.0157 g H₂

Now mass of hydrogen collected is 0.016 gram (rounding the amount)

geosphere and hydrosphere.

this is because the geosphere has to do with geological events, while the hydrosphere controls all water on earth.