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The Bunsen cell generates about 1.9 volts which arises from the following reaction: [1]. Zn + H 2 SO 4 + 2 HNO 3 ⇌ ZnSO 4 + 2 H 2 O + 2 NO 2 (g). According to the reaction above, when 1 mole (or part) each of zinc and sulfuric acid react with 2 moles (or parts) of nitric acid, the resultant products formed are, 1 mole (or part) of zinc sulfate and 2 moles (or parts) each of water and ...
Both flasks are submerged in a dry ice/acetone cooling bath (−78 °C) the temperature of which is being monitored by a thermocouple (the wire on the left). A cooling bath or ice bath , in laboratory chemistry practice, is a liquid mixture which is used to maintain low temperatures, typically between 13 °C and −196 °C.
Zinc nitrate is usually prepared by dissolving zinc metal, zinc oxide, or related materials in nitric acid: Zn + 2 HNO 3 → Zn(NO 3) 2 + H 2 ZnO + 2 HNO 3 → Zn(NO 3) 2 + H 2 O. These reactions are accompanied by the hydration of the zinc nitrate. The anhydrous salt arises by the reaction of anhydrous zinc chloride with nitrogen dioxide: [1]
Zinc is a strong reducing agent with a standard redox potential of −0.76 V. Pure zinc tarnishes rapidly in air, rapidly forming a passive layer. The composition of this layer can be complex, but one constituent is probably basic zinc carbonate, Zn 5 (OH) 6 CO 3. [8] The reaction of zinc with water is slowed by this passive layer.
The reaction produces a primary, secondary, or tertiary alcohol via a 1,2-addition. The Barbier reaction is advantageous because it is a one-pot process: the organozinc reagent is generated in the presence of the carbonyl substrate. Organozinc reagents are also less water sensitive, thus this reaction can be conducted in water.
The term zinc–air fuel cell usually refers to a zinc–air battery in which zinc metal is added and zinc oxide is removed continuously. Zinc electrolyte paste or pellets are pushed into a chamber, and waste zinc oxide is pumped into a waste tank or bladder inside the fuel tank. Fresh zinc paste or pellets are taken from the fuel tank.
It is the oxidation of dissolved or suspended components in water using oxygen as the oxidizer. It is referred to as wet air oxidation (WAO) when air is used. The oxidation reactions occur in superheated water at a temperature above the normal boiling point of water (100 °C), but below the critical point (374 °C).
Preheated air at 190 to 1,050 °C (370 to 1,920 °F) is blown into the bottom of the furnace. Zinc vapour and sulfides leave through the top and enter the condenser. Slag and lead collect at the bottom of the furnace and are tapped off regularly. The zinc is scrubbed from the vapour in the condenser via liquid lead.