Goodbye privacy, hello 'Alexa': Amazon Echo, the home robot who hears it all. We had Rory Carroll invite âAlexaâ aka the Echo into his home. There was helpful cooking assistance, endless facts and figures, an amusing misunderstanding â and concerns over what exactly Amazon does with all that interaction data. Rory Carroll in Los Angeles.
Aqua regia or Royal water can dissolve metals. It is a mixture of conc.nitric acid and conc.hcl in the ratio of 1:3. Remember none of the above mentioned acids will dissolve the metals in the absence of other. adhi Â· 9 years ago.
Popular Terms. Chemical metal cleaning process in which a strong inorganic acid (typically hydrochloric or sulfuric acid) is used at about 80Â°C to strip the surface of dirt, oil, rust, and scale. Usually, a small amount of citric acid is also added to the acid-water solution to serve as a buffering agent that retards metal etching.