Which is amphoteric oxide?

1. ZnO

2. MnO^-₄

3. CO₂

4. SiO

Which is a true acid anhydride?

(1) $A{l}_2{O}_3$

(2) CO

(3) CaO

(4) $C{O}_2$

$$Which of the following best explains the difference in hydrolytic behaviour between CCl₄ and SiCl₄?

1.  Carbon cannot expand its octet but silicon can expand.

2. The electronegativity of carbon is higher than that of silicon

3. The ionization potential of carbon is higher than that of silicon

4.  Carbon forms double and triple bonds, but silicon does not

Which is formed when $SiC{l}_4$ vapours are passed over hot Mg?

(1) $SiC{l}_2+MgC{l}_2$

(2) $Si+MgC{l}_2$

(3) $M{g}_{2}Si+C{l}_2$

(4) $MgSiC{l}_6$

Asbestors is chemically:

1. silicate of calcium and magnesium

2. calcium alumino silicate

3. magnesium alumino silicates

4. calcium silicate + calcium aluminates

Aqueous solution of sodium silicate is:

(1) acidic

(2) alkaline

(3) neutral

(4) insoluble

Quartz is made of silicon and oxygen joined in a network arrangement that is similar to:

1. Diamond

2. Graphite

3. $O_2$

4. None of the above

The product obtained when silica reacts with hydrogen fluoride is:

1. SiF₄

2. H₂SiF₆

3. H₂SiF₄

4. H₂SiF₃

Silica reacts with Mg to form a magnesium compound (A). (A) react with dil. HCl and forms (B). (B) is:

(1) MgSiO

(2) MgO

(3) $MgC{l}_2$

(4) $SiC{l}_4$

Silica is reacted with sodium carbonate. Which is the gas liberated?

(1) CO

(2) $O_2$

(3) $O_3$

(4) $C{O}_2$