Periods

Q.

In the modern periodic table, the period indicates the value of

1. Atomic number

2. Atomic mass

3. Principal quantum number

4. Azimuthal quantum number

Q. What are the trends in the modern periodic table?

Q. Atomic number of Ag is 47. In the same group the atomic number of elements placed above and below Ag will be

1. 37, 67

2. 29, 79

3. 39, 69

4. 18, 28

Q.

Why Does Period 5 Have 18 Elements?

Q.

Total number of orbitals in a shell is given by _____.

Q.

The atomic numbers of three elements A, B and C are 3, 9 and 11 respectively. State which of the two elements will exhibit similar chemical properties.

Q.

Elements A, B and C have atomic numbers 9, 20 and 10 respectively.

State which one is

(1) a non-metal,

(2) a metal,

(3) chemically inert

Q. An element has an atomic number of 107. What is its electronic configuration and what will be its group number?

1. [Rn] 5f¹⁴ 6d¹ 7s² 7p⁴ , group 3

2. [Rn] 5f¹⁴ 7s² 7p⁵ , group 7

3. [Rn] 5f¹⁴ 6d² 7s² 7p³ , group 15

4. [Rn] 5f¹⁴ 6d⁵ 7s² , group 7

Q.

The atom having the number of electron shell as 4 and valence electrons as 2 belongs to

1. Group 13 and period 4

2. Group 14 and period 3

3. Group 3 and period 4

4. Group 4 and period 3

Q. why atomic no. is more preferable than atomic mass ?

Q.

Reference to the long form of the periodic table fills in the blanks with appropriate words.

The______elements are accommodated in the middle of the periodic table.

Q.

The last subshell of an element is 3p and there are 3 electrons in it.

(a) Write the complete electron configuration of the element.

(b) Identify its period and group.

Q. An element X belongs to group fourteen and second period of the periodic table. Its atomic number is:

1. seven
2. eleven
3. fifteen
4. six

Q. Which of the following elements belong to Lanthanide series?

1. Th
2. Ce
3. Mn
4. Hg

Q.

What are periods?

Q.

The atomic number of elements X, Y and Z are (A -2), A and (A + 2), respectively. Y is a noble gas (not helium) then predict the group to which X, Y, and Z belong and also predict the formula of a molecule formed by X and Z?

Q. In the modern periodic table, the periods are represented by:

1. columns
2. diagonal rows
3. individual elements
4. horizontal rows

Q. Atomic number of a few elements are given below 10, 20, 7, 14
(a) Identify the Group number of the element with atomic number 14.
(b) Identify the Periods of these elements in the Periodic Table.
(c) What would be the electronic configuration for element with atomic number 20?
(d) Determine the valency of the element with atomic number 7.

Q. is the longest period in the periodical table.

Q. Electronic configuration of elements P, Q, R and S are given below:
P - (2, 2)
Q - (2, 8, 2)
R - (2, 8, 5)
S - (2, 5)
Which of the following options is correct?

1. P and Q belong to second period and R and S belong to third period.
2. P and R belong to second period and Q and S belong to third period.
3. S and Q belong to second period and R and P belong to third period.
4. P and S belong to second period and R and Q belong to third period.

Q. Assertion :In the same period or subgroup a gradual change in a particular property may be seen Reason: The periodic repetition of the properties of the elements is due to the recurrence of similar valence shellelectronic configurations after certain regular intervals

1. Both Assertion and Reason are correct and Reason is the correct explanation for Assertion
2. Both Assertion and Reason are correct but Reason is not the correct explanation for Assertion
3. Assertion is correct but Reason is incorrect
4. Both Assertion and Reason are incorrect

Q. The highlighted row ‘Aa’ and column ‘Bb’ in the modern periodic table are called _____ and _____ respectively.​

1. groups, periods
2. periods, groups​
3. coloumn, row

Q. An element X belongs to group fourteen and second period of the periodic table. Its atomic number is:

1. six
2. seven
3. eleven
4. fifteen

Q. Which is true about effective nuclear charge?

1. Z_eff decreases from top to bottom

2. =Screening Constant

3. Z_eff increases from top to bottom

4. Z_eff increases as we move from left to right in the Periodic table

Q. Element with the electronic configuration as $[Ar{]}^{18}3d^{5}4s^1$ is placed in?

1. IA, s-block

2. VIA, s-block

3. VIB, s-block

4. VIB, d-block

Q. The ratio of stoichiometric coefficients of triatomic gas to the tetra atomic gas released on thermal decomposition of two moles of ferrous sulphate ?

Q.

An element has an electronic configuration 2, 8, 7. It belongs to the _________________.

1. 17th group & 2nd period

2. 7th group & 3rd period

3. 3rd group & 7th period

4. 17th group & 3rd period

Q.

Give the information conveyed by the symbol ${}_{17}{}^{35}\mathrm{Cl}$.

Q. Why the elements of second row ( first short period ) Show a number of differences in properties from other members of their respective families.

Q.

All elements in 3rd period have

1. An atomic number 3

2. 3 complete sub-shells

3. Valence electrons shell

4. 3 electrons less than the octet