Halogens

Q.

The position of elements A, B, C, D and E in the periodic table are shown below:

$\begin{array}{cccc}Group1& Group2& Group17& Group18\\ -& -& -& D\\ -& B& C& -\\ A& -& -& E\end{array}$

(a) State which are metals, non-metals and noble gas in this table.

(b) State which is the most reactive (i) metal (ii) non-metal

(c) Which type of ion will be formed by element A, B, and C.

(d) Which is larger in size (i) D or E (ii) B or C.

Q. How do we know that which elements are metal and non metal in electronic configuration?

Q. Which of the two would be chemically more reactive element? Element P of atomic number 18 or element Q of atomic number 16? Give reason.

Q.

Which one of the following group 17 elements has the smallest atomic radius?

1. F

2. Cl

3. Br

4. I

Q.

What is the electronic configuration of the second element in the halogen family of the second period?

1. 2, 8, 18, 18, 7

2. 2, 8, 18, 7

3. 2, 8, 7

4. 2, 7

Q.

Pick all the elements that belong to the halogen group.

1. Chlorine

2. Iodine

3. Helium

4. Fluorine

Q.

If the atomic radius of Chlorine is considered to be x, and that of Aluminium is considered to be y. What can you comment about the value of $\frac{x}{y}$?

1. Greater than 1

2. Less than 1

3. Equal to 1

4. Less than 0

Q.

Smita studied about the Modern Periodic Table. She placed hydrogen, lithium, sodium, and calcium in the same group in the periodic table. However, her teacher told her that she has placed one element incorrectly in the periodic table.

(Atomic numbers of H, Li, Na, and Ca are 1, 3, 11, and 20 respectively)

Which element has been placed incorrectly by Smita?

1. Lithium

2. Sodium

3. Hydrogen

4. Calcium

Q.

Write down the symbols for each of the following elements:

1. Iron
2. Gold
3. Sodium
4. Oxygen
5. Carbon
6. Sulphur
7. Silver
8. Calcium

Q.

4. Write the symbols of these elements.

vii. Calcium

Q.

An element in the periodic table has the electronic configuration of 2, 8, 7. Which of the following family does the element belong to?

1. Alkali metals
2. Alkaline earth metals
3. Noble gas
4. Halogens

Q.

State the period which contains the alkali metal lithium, the halogen fluorine and noble gas neon.

Q. There are electrons in the outermost shell of a carbon atom.

1. 2
2. 4
3. 6
4. 8

Q.

The element with controversial placement in modern periodic table is __.

Q.

Explain in detail the controversy behind the placement of Hydrogen in the modern periodic table.

Q. What is the chemical symbol of beryllium?

1. B
2. Br
3. Be
4. Ba

Q.

Among halogens, __has the smallest atomic radius.

Q.

Which one of the following elements is most reactive?

1. Neon

2. Argon

3. Carbon

4. Helium

Q.

If electronic configuration of an atom is 2, 8, 7, how can the group number of that atom be determined?

Q. What is the chemical symbol of beryllium?

1. B
2. Br
3. Be
4. Ba

Q. A beaker containing hot water is kept in the freezer compartment of a refrigerator (temperature < 0 ${}^o$C). If you could measure the temperature of the content of the beaker, which of the following graphs would correctly represent the change in its temperature as a function of time?

Q. Write the symbols for the following elements.
(i) Lithium
(ii) Potassium
(iii) Calcium
(iv) Sulphur
(v) Phosphorous
(vi) Argon
[3 Marks]

Q.

The electronic configuration of element X is K, L, M

2, 8, 2

What is the period number of element X?

Q.

Give the number of the group and the period of the element having three shells with three electrons in the valence shell.

Q.

The element with controversial placement in modern periodic table is __.