1answer.
Ask question
Login Signup
Ask question
All categories
  • English
  • Mathematics
  • Social Studies
  • Business
  • History
  • Health
  • Geography
  • Biology
  • Physics
  • Chemistry
  • Computers and Technology
  • Arts
  • World Languages
  • Spanish
  • French
  • German
  • Advanced Placement (AP)
  • SAT
  • Medicine
  • Law
  • Engineering
puteri [66]
3 years ago
15

The half-life for the first-order decomposition of a is 355 s. how much time must elapse for the concentration of a to decrease

to
a.one-fourth
Chemistry
1 answer:
Eva8 [605]3 years ago
4 0

Given the half life of the first order decomposition reaction is 355 s

Rate constant of the first order reaction is related to the half life by the equation,

k = \frac{0.693}{t_{\frac{1}{2}}}

k = \frac{0.693}{355 s}

k = 0.00195 s^{-1}

The concentration of the substance is decreased to 1/4 th.

If we start with 1 M solution, after time t the concentration becomes 1/4th = 0.25 M

First order rate law:

[A] = [A]_{0} e^{-kt}

[A] = 0.25 M

[A]_{0} = 1 M

k = 0.00195 s^{-1}

Plugging in the values to solve for t,

0.25 M = 1 M (e^{-(0.00195s^{-1})t})

ln(\frac{0.25}{1}) = - (0.00195 s^{-1})(t)

t = \frac{ln(0.25)}{0.00195} s

t = 710 s

You might be interested in
Cycloheptatrienone is stable, but cyclopentadienone is so reactive that it can't be isolated. Taking into account the polarity o
Lorico [155]

Answer and Explanation:

The resonance contributor in cyclopentadienone (as shown in the attachment below) results into the compound having a positive charge on the carbonyl group, C=O which accounts for a highly reactive anti-aromatic 4π system. And this illustrates the reason for its instability.

3 0
3 years ago
Help me with this please ​
Gala2k [10]

Answer:

Gap 1, S-Phase, Gap 2, Prophase, Metaphase, Anaphase, Telophase, Cytokinesis

Hope this helps.

8 0
3 years ago
Which best explains how insects help flowering plants in reproduction?
ankoles [38]

Answer:

if insects helps in pollination that is called entomophily

Explanation:

Some plants having attractive odor and color which attracted the insects towards it and when they come in contact with flowering plant the seed or pollens which is produced by the male part of plant got attached to their body and when insects travels to other flowering plants pollens sheds to stigma which is female part of flower and in results fertilization occur.

4 0
3 years ago
what are some of the relationships among thermal energy, kinetic energy, particle movement, and temperature?
mamaluj [8]

Answer:

Temperature measures the average kinetic energy of the particles in a substance.

Explanation:

Thermal energy measures the total kinetic energy of the particles in a substance. The greater the motion of particles, the higher a substance's temperature and thermal energy.

8 0
2 years ago
Read 2 more answers
What's the meaning of phenolphthalein?
olchik [2.2K]
Phenolphthalein is an indicator used in chemistry to detect acidic or basic/alkaline solutions.It is often used in the lab as an indicator used to carry out accurate titration using soluble reactants.
4 0
3 years ago
Read 2 more answers
Other questions:
  • In the first step of the reaction, which compound is the limiting reagent: sodium hydroxide or the nucleophile
    5·1 answer
  • When 0.50 liter of a 12m solution is diluted to 1.0 liters, the molarity of the new solution is ____
    12·1 answer
  • What is the mass of 2.56 × 10–4 moles of Fe2O3? : 6.23 × 105 159.6 g 1.60 × 0–6 g 4.09 × 10–2 g
    9·1 answer
  • A student wonders whether a piece of jewelry is made of pure silver. She determines that its mass is 3.25 g. Then she drops it i
    15·1 answer
  • Magnesium metal a gray solid, is heated in a crucble in the presence of oxygen
    14·1 answer
  • The carbon dioxide is released when limestone is heated during the<br> production of _____?
    9·1 answer
  • Electrons in Bohr's model of the atom are at the lowest possible energy state when they are
    6·2 answers
  • Which characteristic could distinguish a crystalline solid from an amorphous
    6·1 answer
  • G= 10N/Kg
    9·1 answer
  • How would I Determine the number of moles in 3.51 x 10^23 formula units of CaCl2
    9·1 answer
Add answer
Login
Not registered? Fast signup
Signup
Login Signup
Ask question!