Periodic classification questions | form two Chemistry

An element X with atomic number 16, belongs to:
A. period 3, group III, valency of 2
B. period 3, group VI, valency of 2
C. period 3, group VI, valency of 6
D. period 6, group VI, valency of 6

Answer / Solution

UNSOLVED

The diagram below represents a part of the periodic table. Study it carefully and answer
the questions that follow:

(a)You are given elements D, C, B, A and E which have atomic numbers 1, 10, 14, 16 and 20 respectively. Place the elements in their respective groups and periods in the above periodic table.

(b) From the given elements identify the element with:
(i) an electronegative property ………………………………
(ii) four valency ………………………………
(iii) inert property ………………………………
(iv) alkaline earth metal property ………………………………
(v) a property of burning oxygen to form water ………………………………
(c) (i) Write a chemical formula of a carbonate of element E.
…………………………………………………………………………………
(ii) Write a balanced equation which shows the decomposition of the carbonate
in (c)-(i) above.

Answer / Solution

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Moving across the period in the periodic table:
A. Electronegativity decreases
B. Electronegativity increases
C. Metallic property increases
D. Electropositivity increases

Answer / Solution

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The figure below is part of the periodic table which includes the first twenty elements.The numbers in the table are the atomic numbers of some elements.

(a) (i) For each number, write the symbol of the corresponding element.
1. __________ 2. __________ 4. __________ 6. __________
8. __________ 11. __________ 12. __________ 17. __________
(ii) Write a formula which represents a compound formed between an element
with atomic number 1 and element with atomic number 17. __________
(b) (i) Considering the elements with atomic number 12 and 17, which is a metal
and which is a non-metal.
………………………………………
………………………………………

(ii) What types of oxides are formed by elements with atomic numbers 11 & 12?
………………………………………
………………………………………

Answer / Solution

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Explain, in terms of electronic configurations, why sodium and potassium
elements have similar chemical properties.
 

Answer / Solution

UNSOLVED