Periods in Modern Periodic Table

Q.

How do you arrange elements in order of increasing metallic character?

Q.

What are the three parts of the periodic table?

Q.

Name

(a) An alkali metal in period 3 and halogen in period 2.

(b) The noble gas with 3 shells.

(c) The non-metals present in period 2 and metals in period 3.

(d) The element of period 3 with valency 4.

(e) The elements i period 3 which does not form oxide.

(f) The element of lower nuclear charge out of Be and Mg.

(g) Which has higher E.A., Fluorine or Neon.

(h) Which has maximum metallic character Na, Li or K.

Q.

What are the characteristics of a period?

Q. Choose the correct answer from the options given below:
(i) In the periodic table alkali metals are placed in the group ___________
(a) 1
(b) 11
(c) 17
(d) 18

(ii) Which of the following properties do not match with elements of the halogen family?
(a) They have seven electrons in their valence shell.
(b) They are highly reactive chemically.
(c) They are metallic in nature.
(d) They are diatomic in their molecular form.

Q.

Which of the following statements about the Modern Periodic Table is correct?

1. It has 18 horizontal rows known as Periods

2. It has 7 vertical columns known as Periods

3. It has 18 vertical columns known as Groups

4. It has 7 horizontal rows known as Groups

Q. In the periodic table of the elements in a period from left to right atomic radius increases or decreases?

Q.

The Chemical Formula For Sodium And Sulphur Contains

1. One Sulphur And One Sodium Atoms.

2. One Sulphur And Two Sodium Atoms.

3. Two Sulphur And One Sodium Atoms

4. Two Sulphur And Two Sodium Atoms.

Q. Explain:
(i) Larger the atomic size, more metallic is the element.
(ii) Halogens have high electron affinity.
(iii) Size of atom changes when it loses or gain electron.
(iv) K is more reactive than Li.
(v) Electronegativity of Cl is higher than S.
(vi) Group 17 elements are non-metals, while group 1 elements are metals.

Q. (i) What is the common feature of the electronic configurations of the elements at the end of period 2 and period 3?
(ii) If an element is in group 7 (or Group VIIA), is it likely to be metallic or non-metallic in character?
(iii) Supply the missing word from the words given in brackets.
If an element has one electron in its outermost energy level (shell), then it is likely to be ______ (metallic/non-metallic).

Q.

What are elements $89$ to $103$ called?

Q.

Increasing order of electronegativity is:

1. Si < P < S < Cl

2. Cl < S < Si < P

3. P < Si < S < Cl

4. S < Si < P < Cl

Q. 29.The correct decreasing order of electropositive character among the following elements is : Fe, Rb, Br, Te, F, Ca

Q. How many electrons can be filled in the L shell?

1. Eight
2. Six
3. Two
4. Eighteen

Q.

Consider the following elements :

Na, Ca, Al, K, Mg, Li

(a) Which of these elements belong to the same period of the periodic table?

(b) Which of these elements belong to the same group of the periodic table?

Q. Write scientific reason: The third period contains only eight elements even though the electron capacity of the third shell is 18.

Q. Which element has the largest size in the second period?

1. N
2. F
3. Li
4. Be

Q.

In the modern periodic table, what remains same along the period?

Q.

(a) What are the periods and groups in a periodic table? Give two characteristics of each.

(b) In terms of electronic configurations, explain the variation in the size of the atoms of the elements belonging to the same period and same group.

(c) Given alongside is a part of the periodic table. As we move vertically downward from Li to Fr :

$\begin{array}{cc}Li& Be\\ Na& \\ K& \\ Rb& \\ Cs& \\ Fr& Ra\end{array}$

(i) What happens to the size of atoms?

(ii) What happens to their metallic character?

(d) Name two properties of elements whose magnitudes change when going from top to bottom in a group of the periodic table. In what manner do they change?

(e) Rewrite the following statement after correction, if necessary :

Groups have elements with consecutive atomic numbers.

Q. The atomic radius decreases as we move across a period because

1. atomic mass increases.
2. atomic number increases.
3. effective nuclear charge increases.
4. more electrons are added.

Q.

An atom with 4 protons and 5 neutrons will have a valency of :

1. 1

2. 2

3. 3

4. 4

Q. The number of shells and valence electrons for an element with atomic number 14 are ___ and ___.

1. 2, 4
2. 4, 4
3. 3, 4
4. 4, 3

Q.

Fill in the blanks in the following statements :

(a) The horizontal rows in a periodic table are called .............

(b) In going across a period (right to left) in the periodic table, the atomic size of the atom .............

(c) On moving from right to left in the second period, the number of valence electrons ..............

(d) When we down in a group in the periodic table, the metallic character of elements ..............

(e) The tendency to gain an electron ................ on moving down in a group of the periodic table.

Q.

Which of the following statements about the Modern Periodic Table is correct?

1. It has 18 horizontal rows known as periods .

2. It has 7 vertical columns known as periods .

3. It has 18 vertical columns known as groups .

4. It has 7 horizontal rules known as groups.

Q.

In modern periodic table, the atom of the element present at the end of each period has a/an _____ valence shell.

1. Completely filled

2. Incomplete

3. Half filled

4. Singly occupied

Q.

Assertion: Metallic characters of the elements increases down group while non-metallic character decreases.

Reason: Down the group electron releasing tendency of the element increases while their electron accepting tendency decreases.

Mark the correct choice

1. Both assertion and reason are correct and the reason is the correct explanation of assertion.

2. Both assertion and reason are correct but the reason is not the correct explanation of assertion.

3. Assertion is correct but the reason is incorrect.

4. Assertion is incorrect but reason is correct.

Q.

X- $1s^{2}2s^{2}2p^{6}3s^{2}3p^{6}3d^1$

Y- $1s^{2}2s^{2}2p^{6}3s^{2}3p^{6}4s^1$

Which of the given electronic configuration is correct?

1. X is correct

2. Y is correct

3. Both are correct

4. Both are wrong

Q.

Rewrite the following statements after correction, if necessary :

(a) Groups have elements with consecutive atomic numbers.

(b) Periods are the horizontal rows of elements.

(c) Isotopes are the elements of the same group.

Q.

Why are there no P blocks in period 1?

Q.

Define the periodic table. discuss the structure of the periodic table.