The third law of thermodynamics states that:. a. the entropy of the universe equals the sum of the entropy of system and that of the surroundings.
b. the entropy of the universe is constant.
c. the entropy is zero at 0 K for a perfect crystal.
d. the entropy of the universe is increasing.
e. the absolute entropy of a substance decreases with increasing temperature.

C

Explanation:

The third law of thermodynamics states that at absolute zero temperature, the entropy of a perfect crystal is zero. In other words, as the temperature of a system approaches zero, the entropy also approaches a constant value.

The law only holds true only if the crystal has minimal energy and only exist in one state. The entropy becomes zero as the temperature also becomes zero only for a perfect crystal. Otherwise, the law refuses to hold.

The correct option is, therefore, C.

1.24g

Explanation:

Given parameters:

Mass of titanium (IV) chloride  = 4.6g

Unknown:

Mass of oxygen  = ?

Solution:

To solve this problem, we need to write the balance reaction equation first;

                TiCl₂   +   O₂    →    TiO₂     +   Cl₂

Now to find the mass of the oxygen gas,

Express the given mass of the known TiCl₂ in moles:

         Number of moles of TiCl₂  =

  Molar mass of TiC₂  = 47.9 + 2(35.5) = 118.9g/mol

    Number of moles of TiCl₂   =   = 0.04mole

From the reaction equation;

        1 mole of TiCl₂  reacted with 1 mole of oxygen gas

       0.04 mole of TiCl₂ will react with 0.04 mole of oxygen gas

Mass of oxygen gas  = number of moles x molar mass

              molar mass of oxygen gas  = 2(16) = 32g/mol

  Mass of oxygen gas  = 0.04 x 32  = 1.24g