Chemistry
Five atoms are labelled V to Z
Atoms | Mass Number | Atomic number |
---|---|---|
V | 40 | 20 |
W | 19 | 9 |
X | 7 | 3 |
Y | 16 | 8 |
Z | 14 | 7 |
(i) Which one of these atoms (1) contains 7 protons; (2) has an electronic configuration 2, 7 ?
(ii) Write down the formula of the compound formed by atoms X and Y.
Atomic Structure
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Answer
(i) As Z has atomic number of 7, hence it has 7 protons. Electronic configuration of 2, 7 means the atom has 2 + 7 = 9 electrons. Therefore, element W has electronic configuration 2, 7 since its atomic number is 9.
(ii) Number of electron in X is 3. Therefore, electronic configuration = (2, 1). As X will try to lose 1 electron to attain stable state, hence, X has valency [1+]
Number of electron in Y is 8. Therefore, electronic configuration = (2, 6). As Y will try to gain 2 electrons to attain stable state, hence, Y has valency [2-]
Since valency of X is 1+ and valency of Y is 2-
Formula of the compound:
So, we get the formula as
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Related Questions
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