Advertisements
Advertisements
प्रश्न
Distinguish between:
Group 17 - Group 18
Advertisements
उत्तर
| Group 17 | Group 18 | |
| 1. | Elements of group 17 are called halogens. | Elements of group 18 are called inert gas elements or noble gases. |
| 2. | They have seven valence electrons. | They have eight valence electrons except helium which contains 2 electrons. |
| 3. | Their valency is 1. | Their valency is zero. |
| 4. | They form diatomic molecules with general formula (X2). | They are monoatomic gases under normal conditions. |
APPEARS IN
संबंधित प्रश्न
Write the names given to the vertical columns and horizontal rows in the Modern Periodic Table. How does the metallic character of elements vary on moving down a vertical column? How does the size of atomic radius vary on moving left to right in a horizontal row? Give reason in support of your answer in the above two cases.
How many rows and columns are there in the modern periodic table?
How does the tendency of elements to gain electrons change as we move from left to right in a period? State the reason of this change.
How many periods and groups are there in the long form of periodic table?
Give two example of group 1 elements.
How were the positions of cobalt and nickel resolved in the modern periodic table?
Name the scientist who prepared modern periodic table.
Which of the following statement about the modern periodic table is correct?
(a) It has 18 horizontal rows known as periods.
(b) It has 7 vertical columns known as periods.
(c) It has 18 vertical columns known as groups.
(d) It has 7 horizontal rows known as groups.
Consider the following elements:
Na, Ca, Al, K, Mg, Li
Which of these elements belong to the same group of the periodic table?
How would the tendency to gain electrons change on moving from left to right in a period of the periodic table?
How would the tendency to lose electrons change as we go from left to right across a period of the periodic table?
What is the usual number of valence electrons in the atoms of the last element in a period?
Explain why All the elements of a period have different chemical properties.
Explain why, the first period of the periodic table has only two elements whereas second period has eight elements
What is the number of elements is 1st period the modern periodic table?
What are the groups in a periodic table? Give two characteristics of each.
Define:
Periodic table
Name two elements in halogens.
Name two elements in Inert gas.
Name two elements in each case:
Transition element
Name the type of elements which have outermost shell complete.
Write a short note.
Position of isotopes in the Mendeleev’s and the modern periodic table.
State the modern periodic law.
Name the cation and the anion in the salt – calcium sulphate
Give the symbol and valency of the following element and radical.
Chlorine [Chloride]
Name the following:
The group of the Modern Periodic Table to which calcium [Ca2+] belongs.
How were elements arranged in the long form of the periodic table or the Modern Periodic Table?
p-block is composed of groups 1 and 2.
Write scientific reason.
There was ambiguity about the correct position of hydrogen in Mendeleev’s periodic table.
An X element with atomic number 11 and Y element with atomic number 13 belongs to the third period in the modern periodic table. With this information, give the answers of the below questions.
- Which element has more metallic character from these two elements?
- What is the valency of each X and Y elements?
- Atom size of Y element is smaller than atom size of X element. Explain.
Elements in the modern periodic table are arranged in ______groups and______ periods.
Three elements A, B and C have 3, 4 and 2 electrons respectively in their outermost shell. Give the group number to which they belong in the Modern Periodic Table. Also, give their valencies.
An element X which is a yellow solid at room temperature shows catenation and allotropy. X forms two oxides which are also formed during the thermal decomposition of ferrous sulphate crystals and are the major air pollutants.
- Identify the element X
- Write the electronic configuration of X
- Write the balanced chemical equation for the thermal decomposition of ferrous sulphate crystals?
- What would be the nature (acidic/ basic) of oxides formed?
- Locate the position of the element in the Modern Periodic Table.
Choose an element from period 3 of modern periodic table that matches the description given below in instance. Give a reason for your choice.
It has same valency as Lithium.
Choose an element from period 3 of modern periodic table that matches the description given below in instance. Give a reason for your choice.
It has variable valency and is a member of the Oxygen family (group 16).
Spot the error:
There are 5 periods and 17 groups in the modern periodic table.
A part of modern periodic table is given below. On its basis, answer the following questions:
| Group No. → | 1 | 2 | 13 | 14 | 15 | 16 | 17 | 18 |
| Period ↓ | ||||||||
| 2 | A | B | ||||||
| 3 | E | D | F | C |
Write the molecular formula of the compound formed by the combination:
A and F
A part of modern periodic table is given below. On its basis, answer the following questions:
| Group No. → | 1 | 2 | 13 | 14 | 15 | 16 | 17 | 18 |
| Period ↓ | ||||||||
| 2 | A | B | ||||||
| 3 | E | D | F | C |
Which of the element is a Noble gas?
Define groups of modern periodic table.
Answer the following in respect of element \[\ce{_16^32S}\].
Give its formula with hydrogen.
