In a titration of a solution of unknown concentration of calcium hydroxide against hydrochloric acid (concentration 0.9mol/dm3), 25cm3 of calcium hydroxide was neutralised by 22.5cm3 of hydrochloric acid. Calculate the concentration of the calcium hydroxide solution. Ca(OH)2 + 2HCl -> CaCl2 + 2H2O

Sylvanite is a mineral that contains 28.0% gold by mass. how much sylvanite would you need to dig up to obtain 77.0 g of gold? explain how you got your answer and the steps you took. you

2. how is heavy water different from normal water

Which of the following is not a good technique for managing used oil? a) have specific, labeled catch pans available for technicians who are collecting oil b) spills in your shop and any releases on pavement or outside should be poured down a drain c) do not use oil containers for antifreeze or other non-similar fluids d) be prepared for oil spills with the proper absorbents