Advertisements
Advertisements
Question
How does number of valence electrons vary on moving from left to right in the third period of a periodic table?
Solution
Valence electrons in the same shell (outermost shell) increase progressively by one across the period. The first element of sodium has one valence electron and magnesium has two valence electrons.
APPEARS IN
RELATED QUESTIONS
Correct the statement.
Valency depends upon the number of shells in an atom.
The given table shows elements with the same number of electrons in its valence shell.
| Elements | A | B | C |
| m.p. | 63.0 | 180.0 | 97.0 |
Whether these elements belong to same group or period.
According to atomic structure, what determines which element will be the first and which will be the last in a period?
An element barium has atomic number 56. Look up its position in the periodic table and answer the following question.
What is its valency?
The electronic configuration of an element T is 2, 8, 8, 1.
How many valence electrons are there in an atom of T?
The electronic configuration of an element T is 2, 8, 8, 1.
What is the valency of T?
Name the element which has a total of three shells with five electrons in its valence shell?
Explain why the following statement is not correct:
Atoms of elements in the same group have the same number of electron(s).
Write scientific reason.
Elements belonging to the same group have the same valency.
The metals of Group 2 from top to bottom are Be, Mg, Ca, Sr and Ba. State the common feature in the electronic configuration.
On moving down a group, the number of valence electrons ______.
Sodium and aluminum have atomic numbers 11 and 13, respectively. They are separated by one element in the periodic table and have valencies 1 and 3 respectively. Chlorine and potassium are also separated by one element in the periodic table (their atomic numbers being 17 and 19, respectively) and yet both have valency 1. Explain.
An element ‘A’ belongs to the third period and group 16 of the Periodic Table. Find out the valency of A.
The valence shell of element A contains 3 electrons while the valence shell of element B contains 6 electrons. If A combines with B, the probable chemical formula of the compound is ______
Which one of the following elements exhibits a maximum number of valence electrons?
Correct the statement.
Elements in the same period have the same valency.
An element has 2 electrons in its N shell.
What is the valency of this element?
Answer the following in respect of element \[\ce{_16^32S}\].
What is its valency?
Match the atomic number with the following:
A gaseous element with valency 2.
This question refers to the elements of the Periodic Table with atomic numbers from 3 to 18. Some of the elements are shown by letters, but the letters are not the usual symbols of the elements.
| 3 | 4 | 5 | 6 | 7 | 8 | 9 | 10 |
| A | B | C | D | E | F | G | H |
| 11 | 12 | 13 | 14 | 15 | 16 | 17 | 18 |
| I | J | K | L | M | N | O | P |
Which of these is an element with valency 4?
How does the number of valency vary on moving from left to right in the third period of the periodic table?
