Uses of Argon

Q. The noble gases have closed-shell electronic configuration and are monoatomic gases under normal conditions. The low boiling points of the lighter noble gases are due to weak dispersion forces between the atoms and the absence of other interatomic interactions.
The direct reaction of xenon with fluorine leads to a series of compounds with oxidation numbers $+2,+4$ and $+6.Xe{F}_4$ reacts violently with water to given $Xe{O}_3$. The compounds of xenon exhibit rich stereochemistry and their geometries can be deducted considering the total number of electron pairs in the valence shell.

Argon is used in arc welding because of its

1. Low reactivity with metal
2. Ability to lower the melting point of metal
3. Flammability
4. High caloric value

Q. In nature, metal $A$ is found in a free state while $B$ is found in the form of its compounds. Which will be near to the top of activity series of metals?

1. $A$
2. $B$
3. Both A and B
4. None of the above

Q. The least stable in amongst the following is:

1. $L{i}^{-}$
2. $Be$
3. $B$
4. $C$

Q. $A$, $B$ and $C$ are hydroxy-compounds of the elements $X$, $Y$ and $Z$ respectively. $X$, $Y$ and $Z$ are the same period of the periodic table. $A$ gives an aqueous solution of $pH$ less than seven, $B$ reacts with both strong acids and strong alkalis. $C$ gives an aqueous solution which is strongly alkaline.
Which of the following statements is/are true?
I: The three elements are metals.
II: The electronegativities decrease form $X$ to $Y$ to $Z$
III: The atomic radius decreases in the order $X$, $Y$ and $Z$.
IV: $X$, $Y$ and $Z$ could be phosphorus, aluminium and sodium respectively.

1. I, II, III only correct
2. II, IV only correct
3. II, III, IV only correct
4. I, III only correct

Q. Alkaline earth metals are :

1. dehydrating agent
2. amphoteric
3. reducing agent
4. oxidising agent

Q. In nature, metal $A$ is found in a free state while metal $B$ is found in the form of its compounds. $B$ of these two will be nearer to the top of the activity series of metals.

1. True
2. False

Q. The noble gases have closed-shell electronic configuration and are monoatomic gases used normal conditions. The low boiling points of the lighter noble gases are due to weak dispersion forces between the atoms and the absence of other interatomic interactions.

The direct reaction of xenon with fluorine leads to a series of compounds with oxidation number +2, +4 and +6. $Xe{F}_4$ reacts violently with water to give $Xe{O}_3$. The compounds of xenon exhibit rich stereochemistry and their geometries can be deduced considering the total number of electron pairs in the valence shell.

Argon is used in arc welding because of its

1. low reactivity with metal
2. ability to lower the melting point of metal
3. flammability
4. high calorific value

Q.

Which of the following noble gases is preferably used for providing inert atmospheres during welding metals?

1. Helium

2. Neon

3. Argon

4. Krypton

Q. The noble gases have closed-shell electronic configuration and are monoatomic gases used normal conditions. The low boiling points of the lighter noble gases are due to weak dispersion forces between the atoms and the absence of other interatomic interactions.

The direct reaction of xenon with fluorine leads to a series of compounds with oxidation number +2, +4 and +6. $Xe{F}_4$ reacts violently with water to give $Xe{O}_3$. The compounds of xenon exhibit rich stereochemistry and their geometries can be deduced considering the total number of electron pairs in the valence shell.

Argon is used in arc welding because of its

1. low reactivity with metal
2. ability to lower the melting point of metal
3. flammability
4. high calorific value

Q.

A metal forms ionic compounds with the following non-metals.

(A) Bromine

(B) Oxygen

(C) Iodine

(D) Fluorine

(E) Sulphur

Arrange these non-metals in the decreasing order of the strength of the ionic bonds.

1. DBEAC

2. CAEBD

3. BDEAC

4. CBEAD