Question

The decomposition of X is the first-order reaction. After 60 minutes, X loses its 50% in weight. Find the time it takes to lose 80%.

Answer #1

If 1st order, then:

ln(A) = ln(A0) - kt

A0 = initial concentration, k = rate constant, t = time, A = concentration at time t

so..

t = 60 min, x --> 50% loss so

t 1/2 = ln(2) / K

k = ln(2) / t 1/2 = ln(2) / 60 = 0.011552 1/ min

so..

for 80%:

ln(A) = ln(A0) - kt

80% --> 20% left

ln(0.2*A0) = ln(A0) - 0.011552 * t

ln(0.2*A0) - ln(A0) = - 0.011552 * t

ln(0.2) = - 0.011552 * t

t = ln(0.2) / (-0.011552 ) = 139.321 minutes required

The rate constant for the first-order decomposition of
a compound A in the
reaction 2 A P is k, =3.56 x 10-7 s-1 at 25°C. What is the
half-life of A? What will be the
pressure, initially 33.0 kPa at (a) 50 s, (b) 20 min, (c) 20 h
after initiation of the reaction?

The rate constant for the first-order decomposition of
N2O5 by the reaction
2 N2O5 (g) 4 NO2(g) + O2(g) is k, = 3.38 x 10-5 s
-1 at 25 C. What is the half-life of N2O5?
What will be the partial pressure, initially 500 Torr, at ( a) 50
s; (b) 20 min, (c) 2 hr
after initiation of the reaction?

the decomposition of hydrogen peroxide
H2O2, is first-order reaction. the half-life
of of reaction is 17.0minutes.
a.) What is the rate constant of the reaction?
b.) If you had a bottle of H2O2, how long
would it take for 80% to decompose?

For the first order decomposition of
H2O2(aq), given k = 3.60 x 10-3
s-1 and the initial concentration of
[H2O2]o is 0.882 M, determine
:
(a) the time at which [H2O2]t
decreases to 0.600 M;
(b) what will be the concentration of
[H2O2]t after 225 s and (c) find
the half-life of the reaction.

The first-order decomposition of a colored chemical species, X,
into colorless products is monitored with a spectrophotometer by
measuring changes in absorbance over time. Species X has a molar
absorptivity constant of 5.00x103 cm–1M–1 and the path length of
the cuvette containing the reaction mixture is 1.00 cm. The data
from the experiment are given in the table below.
[X]
(M)
Absorbance (A)
Time (min)
?
0.600
0.0
4.00 x 10-5
0.200
35.0
3.00 x 10-5
0.150
44.2
1.50 x...

A
zero-order reaction is 40% complete at the end of 50 minutes. What
is the value id the rate constant with proper units? In many
minutes will the reaction be 80% complete?

The first order constant is 4.82 x 10-3
s-1 at 70C for the decomposition of the following
reaction: 2N2O5 (g) -> 4NO2 +
O2 (g)
Suppose that you start with .0175M of N2O5
(g)
a.) What is the molarity of N2O5 that
remains after 15 minutes (note: the rate constant is in
seconds)
b.) How many seconds will it take for the quantity of
N2O5 to drop to .015M?
c.) What is the half life of N2O5 at
70C?

The reaction A - B is first order in A. Initially, [A]=0.800 M
and after 54 min., [A] = 0.100 M. At what time (in minutes) is [A]
= 0.040?

The decomposition of A to B is a first-order reaction with a
half-life of 85.9 min when the initial concentration of A is 0.483
M: A → 2B How long will it take for this initial concentration of A
to decrease by 23.0%? PLEASE HURRY I DONT HAVE MUCH TIME TO ANSWER
THIS

- As described in Exercise 14.43, the decomposition of sulfuryl
chloride (SO2Cl2) is a first-order process.
The rate constant for the decomposition at 660 K is 4.5 ×
10–2 s–1.
(a) If we begin with an initial
SO2Cl2 pressure of 450 torr, what is the
pressure of this substance after 60 s?
(b) At what time will the pressure of
SO2Cl2 decline to one-tenth its initial
value?

ADVERTISEMENT

Get Answers For Free

Most questions answered within 1 hours.

ADVERTISEMENT

asked 1 minute ago

asked 16 minutes ago

asked 17 minutes ago

asked 19 minutes ago

asked 26 minutes ago

asked 38 minutes ago

asked 1 hour ago

asked 1 hour ago

asked 1 hour ago

asked 1 hour ago

asked 2 hours ago

asked 2 hours ago