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The table below gives elements represented by letters U V W X Y Z and their atomic numbers.

The table below gives elements represented by letters U V W X Y Z and their atomic numbers.

Use the information to answer the questions below.
(a) In which period do these elements belong ? Give a reason.
(b) How does the atomic radius of W and Y compare ? Explain.
(c ) Give the formula of the compound that could be formed between V and X.
(d) What type of bonding will be present in a compound formed between V and Z. Explain.
(e) Arrange the species U, U^- and U⁺ in increasing order of size.
(f) Which of the ions Y²⁺ and Y^2- is the most stable ? Explain.
(g) Give the formula of
(i) An acidic oxide formed when one of the elements in the table is heated in air.
(ii) A basic oxide formed when one of the elements in the table is heated in air.

Answers

(a) Period II
Has two energy levels
(b) Atomic radius of W is smaller than that of Y
Across the period, electrons are added to the same energy level but the number of
protons in the nucleus increases thus increasing the effective nuclear charge
(c ) VX
(d) Ionic. V ionises by losing three electrons to form V³⁺ while Z ionizes
by gaining an electron to form Z^-
(e) U⁺ , U, U^-
Increasing order of size
(f) Y^2- Has a noble gas structure
(g) (i) WO₂
(ii) V₂O₃

sharon kalunda answered the question on April 1, 2019 at 08:41

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