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प्रश्न
An atom of element E contains 3 protons, 3 electrons and 4 neutrons :
(a) What is its atomic number?
(b) What is its mass number?
(c) Write the electronic configuration of the element E.
(d) State whether element E is a metal or non-metal. Why?
(e) What type of ion, cation or anion, will be formed by an atom of element E? Why
(f) Write the symbol of the ion formed by an atom of element E.
(g) What could element X be?
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उत्तर
(a) Its atomic number is 3.
(b) Mass no. = 3 + 4 = 7
\[{\underset{2}{\text{ K }}\underset{8}{\text{ L }}}\]
(c) Electronic configuration is(d) Element E is a metal because in order to complete its octet, the element loses 1 electron from its outermost orbit and attains a stable configuration with 2 electrons in its first shell. Elements which lose electrons to attain stability are called metals.
(e) A Cation will be formed by an atom of element A because its outermost single electron can be easily donated.
(f) E+
(g) Element X is lithium.
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संबंधित प्रश्न
MATCH THE COLUMNAS
| 1. Jpham Dalton | a. Neutrons |
| 2. Atom | b. Model of the atom |
| 3. Chadwick | c.The atomic theory of matter |
| 4. Rutherfrod | d. Positively charged |
| 5. Protons | e. Electricity neutral |
| 6. Nuclear fusion | f. Generator of electricity |
| 7.Gamma -rays | g. High penetrating power |
| h.Energy in sun |
Write the names of the elements present in the:-
Ammonia
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Fill in the following blanks with suitable words :
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An atom of an element X may be written as `""_9^4"X"`
(a) What does the figure 9 indicate?
(b) What does the figure 4 indicate?
(c) What is the number of protons in atom X?
(d) What is the number of neutrons in atom X?
(e) What is the number of electrons in atom X?
(f) How many electrons are there in the outermost shell of an atom of element X?
(g) Write the symbol of ion formed by an atom of element X.
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| a. Proton | i. Negatively charged |
| b. Electron | ii. Neutral |
| c. Neutron | iii. Positively charged |
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- Subatomic particles
- Nucleus
- Orbits or shells.
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The basic unit of matter is not capable of independent existence.
The smallest particle of matter that can exist by itself is ______.
State true or false. If false, correct the statement.
The basic unit of an element is molecule.
Define the following term with an example.
Non-metal
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