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Question
Five atoms are labeled A to E
|
Atoms |
Mass No |
Atomic No. |
|
A |
40 |
20 |
|
B |
19 |
9 |
|
C |
7 |
3 |
|
D |
16 |
8 |
|
E |
14 |
7 |
(a) Which one of these atoms:
(i) contains 7 protons
(ii) has electronic configuration 2,7
(b) Write down the formula in the compound formed between C and D
(c) Predict : (i) metals (ii) non-metals
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Solution
(a)
Atom E contains 7 protons.
Atom B has an electronic configuration 2, 7.
(b) Atom C stands for7Li3, Atom D stands for 8O16.
Hence, compound formula is Li2O.
(c) Metals: A and C, Non-metals: B, D, E
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RELATED QUESTIONS
The following table shows the electronic configuration of the elements W, X, Y, Z:
|
Element |
W |
X |
Y |
Z |
|
Electronic |
2,8,1 |
2,8,7 |
2,5 |
1 |
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|
Element Symbol |
Atomic Number |
Mass Number |
Numbers of neutrons |
Number of Electrons |
Number of Protons |
|
Li |
3 |
6 |
|
|
|
|
Cl |
17 |
|
20 |
|
|
|
Na |
|
|
12 |
|
11 |
|
Al |
|
27 |
|
|
13 |
|
S |
|
32 |
16 |
|
|
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\[\ce{^12_6C}\]
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