Question

What is the percent by mass of titanium in rutile, a mineral that contains titanium and oxygen, if structure can be described as a closed packed array of oxide ions, with titanium in one half of the octahedral holes. What is the oxidation number of titanium?
A. \[ \approx 30\% , + 4\]
B. \[ \simeq 60\% , + 2\]
C. \[ \simeq 60\% , + 4\]
D. \[ \simeq 30\% , + 2\]

Answer 1

Hint: We need to know that titanium is the chemical compound having the symbol $'Ti'$ with atomic number \[22\]. And titanium is a lustrous transition metal having silver colour. The density of titanium is very low and the strength of this metal is very high. The titanium is used as a corrosion resistant in aqua regia, sea – water and chlorine. And this is also used for the preparation of prosthetics, jewelry, scissors etc.

Complete answer:
The percent mass of titanium is not equal to \[30\]. Hence, option (A) is incorrect.
The oxidation number of titanium is not equal to \[ + 2\]. Hence, option (B) is incorrect.
The rutile is a mineral of titanium dioxide and it is the natural form of titanium dioxide, \[Ti{O_2}\]it has a tetragonal crystal system. And here the coordination number of titanium cations is six. The titanium is surrounded with octahedral six oxygen atoms with coordination number three. And the mineral contains both titanium and oxygen. Hence, the percent mass of titanium can be find out by using the formula,
\[percentmassofTi = 48 \times \dfrac{{100}}{{80}} = 60\]
\[48\] is the sum of atomic weight of titanium and oxygen and \[80\] is the molecular weight of titanium dioxide. Thus, the percent mass of titanium is \[60\].
And the oxidation state of titanium is equal to \[ + 4\]. Hence, option (C) is correct.
The percent mass of titanium and oxidation number of titanium is not equal to \[ \simeq 30\% , + 2\]Hence option (D) is incorrect.

So, the correct answer is “Option C”.

Note:
As we know that during a chemical reaction, the oxidation state of an atom, molecule or ion may change. The number of electrons either lost or gained by an atom to form a chemical bond is known as oxidation number. It may increase or decrease the oxidation number by losing or gaining the electrons. The oxidation – reduction reaction is also known as redox reaction. This is a type of chemical reaction that undergoes the transfer of electrons between two species.