The Gas-Phase Decomposition of SO₂Cl₂ Is a First Order Reaction

The gas-phase decomposition of SO₂Cl₂ is a first order reaction as shown below:
SO₂Cl₂ (g) →SO₂ (g) + Cl₂ (g) What is the rate constant , k , of this reaction when the half-life equals 2.3×10⁵ seconds?

A) 4.3×10 ^{- 6} sec ^{- 1}
B) 3.0×10 ^{- 6} sec ^{- 1}
C) 1.2×10⁵ sec ^{- 1}
D) 1.6×10⁵ sec ^{- 1}
E) 3.3×10⁵ sec ^{- 1}