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प्रश्न
Find the correlation:
Mendeleev’s periodic table : atomic mass : : Modern periodic table : _______
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उत्तर
Mendeleev’s periodic table : atomic mass : : Modern periodic table : atomic number
Explanation:
Mendeleev organised his periodic table based on the atomic mass of elements. In contrast, the modern periodic table is based on the atomic number (the number of protons), which Henry Moseley demonstrated to be a more fundamental property for predicting periodic trends in chemical behaviour.
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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 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.
State modern periodic law.
Fill in the following blank with suitable word:
Group 17 elements are known as ...............
Give two example of group 1 elements.
How were the positions of isotopes of an element decided in the modern periodic table?
The atomic numbers of four elements P, Q, R and S are 6, 8, 14 and 16 respectively. Out of these, the element known as metalloid is:
(a) P
(b) Q
(c) R
(d) S
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 period of the periodic table?
How does the chemical reactivity of the halogens vary on going in group 17 of the periodic table?
How do the atomic radii of elements change as we go from left to right in a period of the periodic table?
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 are the advantages of the periodic table?
What are the periods in a periodic table? Give two characteristics of each.
The following diagram shows a part of the periodic table in which the elements are arranged according to their atomic numbers. (The letters given here not the chemical symbols of the elements):
| a 3 |
b 4 |
c 5 |
d 6 |
e 7 |
f 8 |
g 9 |
h 10 |
|
| i 11 |
j 12 |
k 13 |
l 14 |
m 15 |
n 16 |
o 17 |
p 18 |
(i) Which element has a bigger atom, a or f?
(ii) Which element has a higher valency, k or o?
(iii) Which element is more metallic i or k?
(iv) Which element is more non-metallic, d or g?
(v) Select a latter which represents a metal of valency 2.
(vi) Select a letter which represents a non-metal of valency 2.
Name the type of elements which have two outermost shell incomplete.
Name the type of elements which have two electrons in the outermost orbit.
Name an alkali metal in period 3 and halogen in period 2.
How will the tendency to gain electrons change as we go from left to right across a period? Why?
Write a short note.
Position of isotopes in the Mendeleev’s and the modern periodic table.
How many periods and groups are there in the modern periodic table?
Two elements P and Q belong to the same period of the modern periodic table and are in group 1 and group 2, respectively. Compare the following characteristics in the tabular form.
- Number of electrons in their atoms
- Their tendency to lose electrons
- Their metallic characters
- Formation of their oxides
- Formulae of their chlorides
Give the symbol and valency of the following element and radical.
Zinc
Give the symbol and valency of the following element and radical.
Nitrogen [Nitride]
Give the symbol and valency of the following element and radical.
Nitrate
Give the symbol and valency of the following element and radical.
Bisulphate
Give the chemical formula of carbonic acid
Complete the following flow chart.
The inert gas which lies in the third period is ______
The elements A, B, C, D and E have atomic number 9, 11, 17, 12 and 13 respectively. Which pair of elements belong to the same group?
Which of the following elements does not lose an electron easily?
The three elements A, B and C with similar properties have atomic masses X, Y and Z respectively. The mass of Y is approximately equal to the average mass of X and Z. What is such an arrangement of elements called as? Give one example of such a set of elements.
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.
Noble gases are placed in the ______ group in the modern periodic table.
Spot the error:
The elements of group 13 are called the carbon family.
Name the metalloids in the first twenty elements.
Name the following metal:
A metal present in period 3, group 1 of the periodic table.
Answer the following in respect of element \[\ce{_16^32S}\].
Give its electronic configuration.
