Advertisements
Advertisements
Question
Give a reason why elements need to be properly classified.
Advertisements
Solution
Reason of classification of elements:
- It makes the study of elements in an organized manner.
- To help and correlate the properties of elements with the fundamental properties of different states of matter.
- To help to define the relationship of one element with others.
APPEARS IN
RELATED QUESTIONS
The element X forms a compound X2Y. Suggest an element that Y might be and give reasons for your choice.
Atoms of eight elements A, B, C, D, E, F, G and H have the same number of electron shells but different number of electrons in their outermost shells. It was found that elements A and G combine to form an ionic compound. This ionic compound is added in a small amount to almost all vegetables and dishes during cooking. Oxides of elements A and B are basis in nature while those of elements E and F acidic. The oxide of element D is, however, almost neutral. Based on the above information, answer the following questions:
(a) To which group or period of the periodic table do these elements belong?
(b) What would be the nature of compound formed by a combination of elements B and F?
(c) Which two of these elements could definitely be metals?
(d) Which one of the eight elements is most likely to be found in gaseous state at room temperature?
(e) If the number of electrons in the outermost shell of elements C and G be 3 and 7 respectively, write formula of the compound formed by the combination of C and G.
Rearrange the columns 2 and 3 so as to match with the column 1.
| Column 1 | Column 2 | Column 3 |
| i. Triad | a. Lightest and negatively charged particle in all the atoms | 1. Mendeleev |
| ii. Octave | b. Concentrated mass and positive charge | 2. Thomson |
| iii. Atomic number | c. Average of the first and the third atomic mass | 3. Newlands |
| iv. Period | d. Properties of the eighth element similar to the first | 4. Rutherford |
| v. Nucleus | e. Positive charge on the nucleus | 5. Dobereiner |
| vi. Electron | f. Sequential change in molecular formulae | 6. Moseley |
The number of electrons in the outermost shell of alkali metals is ______.
Write the name.
The atom having smallest atomic radius from group 1.
The atom of an element has electronic configuration 2, 8, 7. To which of the following elements would it be chemically similar?
Which of the following is a transition element?
The element with atomic number 26 will be found in group ______
What type of oxide would Eka– aluminium form?
Identify and name the metals out of the following elements whose electronic configurations are given below.
- 2, 8, 2
- 2, 8, 1
- 2, 8, 7
- 2, 1
