12 g of commercial zinc is made to react with excess dilute H2SO4 .The total volume of hydrogen gas liberated was found to be 4.2 litres at 520 mmHg pressure and 279 K. Determine the percentage purity of the zinc.

What is the relation between concentration of reactants and the rate of chemical reaction?

Using data from seismic waves, geologists have learned that earth’s interior is made up of several

Need what is special about water as a compound? how does water regulate climate? what drives water evaporation?   why is the water vapor fresh water when it rises from the ocean? why might freshwater in the form of snow take longer to enter the water cycle again than liquid precipitation?   what is an aquifer? what role do people play in the water cycle? plz just answer as many as you can ! thx if you !