Covalent Bond

Q.

Define mono-valent, divalent and trivalent elements with example?

Q.

What Is the kernel?

Q.

If an atom has four electrons in its valence shell, what type of ions will it form?

Q.

Why chlorine didn't take part in the formation of hydrogen bonding??

Q. The number of electron pairs involved in the formation of a triple bond are ________.

1. three
2. six
3. four
4. two

Q.

What is the number of valence electrons in chlorine?

Q.

What is polar solution and non-polar solution?

Q. What are the factors affecting chemical reactions?

1. Concentration
2. Colour
3. Particle size
4. Temperature
5. Surface area
6. Odour
7. Pressure
8. Catalyst

Q.

Which element has four valence electrons?

1. Sodium

2. Oxygen

3. Carbon

4. Potassium

Q. The energy required to remove electron(s) from the outermost shell is called its ionisation energy.

1. True
2. False

Q.

Why is valency always a whole number?

Q.

The valency of sulphate ion is _____.

Q.

Atoms achieve octet by:

1. Gaining electrons

2. Sharing electrons

3. All of these

4. Losing electrons

Q.

Hydrogen forms only one bond, valency of hydrogen is -

1. 1

2. -1

3. 7

4. 2

Q.

What is the definition of valency?

Q.

We write oxygen as ${\mathrm{O}}_2$ because but why not we write phosphorus as ${\mathrm{P}}_3$ while we write it as ${\mathrm{P}}_4$?

Q.

Translate the following statement into a word equation and then write a balanced chemical equation for the same.

(i) Phosphorus burns in the presence of chlorine to form phosphorus pentachloride.

(ii) Magnesium reacts with hydrochloric acid to give magnesium chloride and hydrogen.

Q.

How many double bonds are present in the molecule of $HN{O}_3$?

1. One

2. Two

3. Three

4. None

Q.

Differentiate between valency and oxidation state

Q. Covalent compounds have generally low melting and boiling points.

1. True
2. False

Q. Maximum covalency of nitrogen is:

1. $6$
2. $3$
3. $5$
4. $4$

Q. What is covalency?

Q. Among the following options, which molecule contains both ionic and covalent bonds?

1. $C_6{H}_{14}$
2. $MgC{l}_2$
3. $(N{H}_4{)}_{2}S{O}_4$
4. $H_{2}O$
5. $C_2{H}_4$

Q. Covalency of nitrogen in ammonium ion is:

1. $2$
2. $3$
3. $4$
4. $5$

Q.

Write the balanced chemical equation of the reaction of nitrogen react with hydrogen.

Q. On combining with other elements chlorine acquires the electronic configuration of ___.

1. argon
2. krypton
3. xenon
4. neon

Q.

Translate the following statement into a word equation and then write a balanced chemical equation for the same.

(i) Phosphorus burns in the presence of chlorine to form phosphorus pentachloride.

(ii) Magnesium reacts with hydrochloric acid to give magnesium chloride and hydrogen.

Q.

What is a covalent bond? How $H_2$ molecules are formed?

Q.

Some atoms attain their inert gas configuration by sharing of electrons. This method of attaining inert gas configuration is known as :

1. covalency
2. electrovalency
3. stabilisation
4. inertness

Q. Boron cannot form which one of the following anions?

1. $B{F}_6^{3-}$
2. $B(OH{)}_4^{-}$
3. $B{O}_2^{-}$
4. $B{H}_4^{-}$