SECTION DATE RELATIONSHIPS IN T Hreriment 19 PERIODIC TABLE PRELIMINARY QUESTION
ID: 229381 • Letter: S
Question
SECTION DATE RELATIONSHIPS IN T Hreriment 19 PERIODIC TABLE PRELIMINARY QUESTIONS o characteristics common to all elements in Group VIIA. t a) List tw two characteristics common to all elements in Group IA, excluding hydrogen 2 What is meant by periodicity of properties? s cousedt 3. Contrast metals and non-metals. lder periodic tables were based upon listing elements by increasing atomic weights. The modern table is based upon increasing atomic numbers. On a modern table, ignoring the lanthanide and actinide ements, find and list three pairs of elements that would be in revere order on a table based on atomic weights. 227Explanation / Answer
1.a) Group VII A elements are halogens i.e. F, Cl, Br, I, At.
General electronic configuration = ns2np5.
i) In halogens last electrons enters in the p-orbitals.
ii) Halogens require one electron to complete its octet or to attain stable noble gas configuration.
b) Group VII A elements are halogens i.e. Li, Na, K, Rb, Cs,Fr.
General electronic configuration = ns1.
i) In halogens last electrons enters in the s-orbitals.
ii) Halogens lose one electron to attain stable noble gas configuration.
Q.3 Metals :- (1) Metals are good conductors of heat and electricity.
(2) These are malleable mean these can be drawn into sheet.
(3) These are ductile mean these can be streached into wire.
(4) Metals are lustrous.
(5) Thses are solid at room temperature.
Non-Metals :- (1) Metals are poor conductors of heat and electricity.
(2) These are brittle.
(3) These are non-ductile.
(4) Non-metals are non-lustrous.
(5) Thses are solid,liquid and gases at room temperature.
Q.5 a) 3rd noble gar is Argon
Q.5 a) 3rd noble gar is Argon
b) Fourth halogens is bromine
c) Heaviest alkali metal without d-electrons is lithium.
d) Seventh transition metal is cobalt
e) Fifth alkaline-metal is barium
f) Fourth element of the fourth period is titanium.
Related Questions
Navigate
Integrity-first tutoring: explanations and feedback only — we do not complete graded work. Learn more.