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प्रश्न
Find the odd one out and give its explanation.
पर्याय
Na
K
Cu
Li
उत्तर
Cu
Explanation-
Copper (Cu) is a less reactive metal while others are highly reactive metals.
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संबंधित प्रश्न
A man went door to door posing as a goldsmith. He promised to bring back the glitter of old and dull gold ornaments. An unsuspecting lady gave a set of gold bangles to him which he dipped in a particular solution. The bangles sparkled like new but their weight was reduced drastically. The lady was upset, but after a futile argument, the man beat a hasty retreat. Can you play the detective to find out the nature of the solution he had used?
Name two metals which are highly resistant to corrosion.
How is sodium metal extracted? Explain with the help of equation of the reaction involved.
Manganese metal is extracted from manganese dioxide by a reduction process by making use of:
(a) carbon
(b) hydrogen
(c) electrolysis
(d) aluminium
The metal which can be extracted from pyrolusite ore is:
(a) mercury
(b) manganese
(c) aluminium
(d) magnesium
Give reasons, why aluminum is used in:
In making ships
Answer the following questions based on the extraction of aluminium from alumina by Hall - Heroult’s Process :
Name the electrode, from which aluminium collected.
What is galvanized iron.
Complete the incomplete statement with missing word:
Metals form positive ions while non- metals ______.
X is an element in the form of a powder. X burns in oxygen and the product is soluble in water. The solution is tested with litmus. Write down only the word which will correctly complete each of the following sentences:
(a) If X is a metal, then the litmus will turn ______.
(b) If X is a non-metal, then the litmus will turn ______.
(c) If X is a reactive metal, then ______ will be evolved, when X reacts with dilute sulphuric acid.
(d) If X is a non -metal, it will form _ oxide, which will form ______ solution with water.
(e) If X is a non -metal, it will not conduct electricity unless it is carbon in the form of ______.
To protect iron from rusting, it is coated with a thin layer of zinc. Name the process.
Which one of the following is not true of metal :
Metal will have 1 or 2 or 3 electrons in their valence shell.
Complete the following by selecting the correct option from the choices given:
The metal which does not react with water or dilute H2SO4 but reacts with concentrated H2SO4 is _________
Define calcination.
Zinc blende is converted to oxide by ______ process.
Froth floatation process is generally used to concentrate ______ ores.
Name the process used for the enrichment of sulphide ore.
Identify who I am!
Ore of Aluminum- ______
On the basis of reactivity metals are grouped into three categories:
- Metals of low reactivity
- Metals of medium reactivity
- Metals of high reactivity
Therefore metals are extracted in pure form from their ores on the basis of their chemical properties.
Metals of high reactivity are extracted from their ores by electrolysis of the molten ore.
Metals of low reactivity are extracted from their sulphide ores, which are converted into their oxides. The oxides of these metals are reduced to metals by simple heating.
(a) Name the process of reduction used for a metal that gives vigorous reaction with air and water both.
(b) Carbon cannot be used as a reducing agent to obtain aluminium from its oxide? Why?
(c) Describe briefly the method to obtain mercury from cinnabar. Write the chemical equation for the reactions involved in the process.
OR
(c) Differentiate between roasting and calcination giving chemical equation for each.
