Nov.+21+answers

Pg. 381 #1-5 Nov. 21/07


 * 1.** Terms are called first-order, second-order, ect. because of the exponent the initial concentration of a reactant is raised to. For example, a first-order reaction would be r ∞ [A]¹, it is first order in respect to the [A]. A second-order reaction would be r ∞ [A]².

//b)// If the [Cl2(g)] was doubled, the rate would also double. //c)// If the [NO(g)]² was tripled, the rate would have to be multiplied by 9. //d)// r = k [Cl2(g)] [NO(g)]² 00.242 mol/(L·s) = k [0.20 mol/L] [ 0.20 mol/L] 30.25 L²/(mol²·s) = k (textbook answer k = 3.0 L/(mol·s)) //e)//r =3.00 [0.44 mol/L] [0.025 mol/L]² r =8.25 x 104 mol/(L·s)
 * 2.** //a)// [Cl2(g)] is first order reaction. [NO(g)]² is second order reaction.

//b)// k t½ =0.693 (1.40 a-1) t½ =0.693 t½ =0.495 a //c)// (assuming a stands for annums which means years) number of half-lives in 2.0 years =2.0 a / 0.495 a number of half-lives in 2.0 years =4 half-lives m =20 g x (½)⁴ m =1.22 g (textbook answer 2.5 g)
 * 3.** //a)// r = k [Antibiotic]

number of half-lives in 1.84 x 10^6 a =8 half-lives m =10.0 g x (½)^8 m =0.039 g
 * 4.** number of half-lives in 1.84 x 10^6 a =1.84 x 10^6 a / 2.3 x 10^5 a

__[H2O2] | Rate (1/t)__ 0.0042 | 0.0140 0.0018 | 0.0059 Difference: (2.3)^m 2.3 m =1 The reation is first-order of reaction in respect to the [H2O2].
 * 5.** Rate =1/t

These answers have been posted by Chris Johnson