Advertisements
Advertisements
Question
Zinc liberates hydrogen gas when reacted with dilute hydrochloric acid whereas copper does not. Explain why?
Solution
Zinc (Zn) is placed above hydrogen in the activity series. It therefore, displaces hydrogen from dilute HCl.
`"Zn"("s") + 2"HCl"("aq") -> "ZnCl"_2("aq") + "H"_2("g")`
Copper is placed below hydrogen and therefore, does not react with dilute HCl.
Cu (s) + HCl (aq) → No action.
APPEARS IN
RELATED QUESTIONS
What is an oxidation reaction? Identify in the following reaction (i) the substance oxidised, and (ii) the substance reduced:
ZnO + C → Zn + CO
When copper powder is heated strongly in air, it forms copper oxide. Write a balanced chemical equation for this reaction. Name (i) substance oxidised, and (ii) substance reduced.
Electrolysis is a redox process. Explain.
With reference to oxidation & reduction reaction – complete the statement given by filling in the blanks with only the words (a) Addition (b) Removal.
‘Oxidation is a chemical reaction involving ____ of oxygen to a substance or ____ of hydrogen from a substance. Reduction on the otherhand involves ____ of hydrogen to a substance or ____ of oxygen from a substance.
Select the correct answer from the symbol in the bracket.
The element, which like hydrogen is a strong reducing agent.
Identify the reducing agent in the following reactions -
`"H"_2"O" + "F"_2 -> "HF" + "HOF"`
Which among the following are physical or chemical change?
Heating of an iron rod to red hot
Which among the following are physical or chemical change?
Curding of milk
During the reaction of some metals with dilute hydrochloric acid, following observations are made.
Some bubbles of a gas are seen when lead (Pb) is reacted with the acid.
Explain this observation giving suitable reason.
The formation of brown colour on the freshly unit surface of vegetables and fruits is because ______ of organic compounds present in them.