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Question
Moseley’s periodic table is based on atomic mass.
Options
True
False
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Solution
False
Correct Statement: Moseley’s periodic table is based on atomic number.
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RELATED QUESTIONS
An element Y is in second period and group 16 of the periodic table:
(i) Is it a metal or non-metal?
(ii) What is the number of valence electrons in its atom?
(iii) What is its valency?
(iv) What is the name of the element?
(v) What will be the formula of the compound formed by Y with sodium?
The following diagram shows a part of the periodic table containing first three periods in which five elements have been represented by the letters a, b, c, d and e (which are not their chemical symbols):
-
1 18 a 2 13 14 15 16 17 b c d e
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(ii) Select the letter which represents a nobles gas.
(iii) Select the letter which represents a halogen.
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(v) What type of bond is formed between d and e?
An element X (atomic number 17) reacts with an element Y (atomic number 20) to form a compound.
(a) Write the position of these elements in the modern periodic table.
(b) Write the formula of the compound formed.
Justify your answer in each case.
Choose the correct option and rewrite the statement.
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State whether true or false. If false, correct the statement.
Metals can gain electrons.
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