Magnesium forms the following compounds: Magnesium oxide — MgO Magnesium hydroxide — Mg(OH) 2 Magnesium sulphate — MgSO 4 If radium too belongs to the same group as magnesium, what would be the formula of radium oxide, radium hydroxide and radium sulphate?

The elements belonging to the same group have the same number of valence electrons. Therefore, the same group members will have the same valency and oxidation state. Here, magnesium belongs to the second group, has an oxidation state of + 2 and therefore radium will also have an oxidation state of + 2. Thus, the formula for radium compounds are as follows: Radium oxide - RaO Radium hydroxide - Ra ( OH ) 2 Radium sulphate - RaSO 4 .

For the main groups of the periodic table, the metallic properties of the elements vary approximately with their position as shown in the chart below (a) Where will you find the most metallic element? (b) Where will you find the most nonmetallic element? (c) Where will you find the smallest atom?

(a) The most metallic element will be found on the left side of the table and the element is C that is sodium. The metallic character increases as we move down a group. This is because electrons become easier to lose as the atomic radius increases. (b) The most non-metallic elements will be found on the right side of the table and the element is B that is fluorine. The electronegativity is more for fluorine. The electronegativity is directly related to the non–metallic character of elements. (c) The smallest atom will be on the left side of the table that is hydrogen H.

E M B I B E

Foundation Science Chemistry FOR CLASS 10>Chapter 1 - Periodic Classification of Elements>EXERCISES>Q 7

EASY

10th CBSE

IMPORTANT

Earn 100

State the modern periodic law.

Important Questions on Periodic Classification of Elements

MEDIUM

10th CBSE

IMPORTANT

Foundation Science Chemistry FOR CLASS 10>Chapter 1 - Periodic Classification of Elements>EXERCISES>Q 8

What is a period in a periodic table? How does the electronic configuration change in a period with increase in atomic number from left to right?

MEDIUM

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IMPORTANT

Foundation Science Chemistry FOR CLASS 10>Chapter 1 - Periodic Classification of Elements>EXERCISES>Q 9

Discuss two advantages of the periodic table.

HARD

10th CBSE

IMPORTANT

Foundation Science Chemistry FOR CLASS 10>Chapter 1 - Periodic Classification of Elements>EXERCISES>Q 10

Magnesium forms the following compounds:
Magnesium oxide — MgO
Magnesium hydroxide — Mg(OH)₂
Magnesium sulphate — MgSO₄

If radium too belongs to the same group as magnesium, what would be the formula of radium oxide, radium hydroxide and radium sulphate?

HARD

10th CBSE

IMPORTANT

Foundation Science Chemistry FOR CLASS 10>Chapter 1 - Periodic Classification of Elements>EXERCISES>Q 11

For the main groups of the periodic table, the metallic properties of the elements vary approximately with their position as shown in the chart below

Question Image
(a) Where will you find the most metallic element?
(b) Where will you find the most nonmetallic element?
(c) Where will you find the smallest atom?

MEDIUM

10th CBSE

IMPORTANT

Foundation Science Chemistry FOR CLASS 10>Chapter 1 - Periodic Classification of Elements>EXERCISES>Q 12

Name two other elements which are in the same family as
(a) carbon
(b) fluorine and
(c) sodium.

MEDIUM

10th CBSE

IMPORTANT

Foundation Science Chemistry FOR CLASS 10>Chapter 1 - Periodic Classification of Elements>EXERCISES>Q 13

Write the names of first four members of the halogen family. Write their symbols in the order of increasing atomic number. How are their melting points expected to be related to their atomic numbers?

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10th CBSE

IMPORTANT

Foundation Science Chemistry FOR CLASS 10>Chapter 1 - Periodic Classification of Elements>EXERCISES>Q 14

From their positions in the periodic table, select the atom with the larger size in each of the following pairs:
(a) Li and Be
(b) Na and Mg
(c) Cl and I
(d) B and C

MEDIUM

10th CBSE

IMPORTANT

Foundation Science Chemistry FOR CLASS 10>Chapter 1 - Periodic Classification of Elements>EXERCISES>Q 15

In what respect does modern statement of the periodic law differ from that stated in Mendeleev’s periodic law?