P-1 Periodic Classification of Element — Science STD 10 — Question

Describe Hall’s process for concentration of bauxite.

In what respects do the properties of group 1 elements differ from those of group 17 elements? Explain with examples by taking one element from each group.

How the excessive use of social media and technology is proving harmful?

Draw a neat labelled diagram : Magnetic separation method

Write the characteristics of vertebrates.

Give three examples of materials that refract light rays. What happens to the speed of light rays when they enter these materials?

Write the factors affecting environment.

Answer the questions based on Modern Periodic table.
(i) On going through the Modern Periodic table (fig 2.1) it is seen that the elements Li, Be, B, C, N, O, F and Ne belong to the period-2. Write down the electronic configuration.
(ii) Is the number of valence electrons same for all these elements?
(iii) Is the number of shell the same in these ?

XY compound is formed by X (Atomic number 11) and Y (Atomic number 17), then answer the questions given below.

1. Determine the position of the element X and Y periodic table.
2. X and Y belongs to which of the following: metals, nonmetals or metalloids?
3. From which block the elements X and Y are?
4. Determine the electronic configuration and valency of these elements.