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
Annette [7]
3 years ago
8

A certain first-order reaction (A→products) has a rate constant of 7.20×10−3 s−1 at 45 ∘C. How many minutes does it take for the

concentration of the reactant, [A], to drop to 6.25% of the original concentration?
Express your answer with the appropriate units.
Chemistry
1 answer:
lesya692 [45]3 years ago
6 0

Answer:

6,41 min

Explanation:

For the reaction:

A → products

kinetics first-order reaction law is:

ln[A] = ln[A]₀ -kt

Where [A] is concentration of reactant, [A]₀ is initital concentration of reactant, k is rate constant and t is time.

If the concentration of A is 6,25% you can assume:

[A] = 6,25; [A]₀= 100. Replacing:

ln(6,25) = ln(100) -7,20×10⁻³s⁻¹t

-2,7726 = -7,20×10⁻³s⁻¹t

385s = t

In minutes:

385s×\frac{1min}{60s} = <em>6,41 min</em>

<em></em>

I hope it helps!

You might be interested in
Determine how much energy is needed to change 50 g of liquid water at 100°C to steam.
marin [14]

Answer:

Q=113,000J

Explanation:

Hello there!

In this case, since the vaporization process is carried out in order to turn a liquid into a gas due to the addition of heat, we can use the following heat equation involving the heat of vaporization of water or any other substance:

Q=m*\Delta _{vap}H

Thus, since this heat of vaporization for water is 2259.36 J/g, we plug in this amount to obtain the total energy for this process.

Q=50*2259.36 J/g\\\\Q=113,000J

Which is positive due to the necessity of heat.

Regards!

5 0
3 years ago
What is the value of x in the equation below?
Colt1911 [192]
If the question includes x only than it’s value would be 1
8 0
3 years ago
Read 2 more answers
Two methods by which we can conserve water and water the plants.
Natalka [10]

Answer:

Two methods which help us to conserve water are:

Sprinkler irrigation system: this irrigation has an arrangement of vertical pipes with rotating nozzles on the top. It is more useful in the uneven and sandy land where sufficient water is not available.

Drip irrigation system: this irrigation system has an arrangement of pipes or tubes with very small holes in them to water plants drop by drop just at the base of the root. It is very efficient as water is not wasted at all.

3 0
2 years ago
Antacid tablets commonly contain calcium carbonate and/or magnesium hydroxide. draw the lewis structure for calcium carbonate an
Katyanochek1 [597]
<span>Tums are great antiacid tablets for heartburn and indigestion. Calcium carbonate is a great chemical to treat these conditions. If it were not for calcium carbonate, then many people would have heartburn for years until they eventually died from the condition unfortunately.</span>
7 0
3 years ago
Al(OH)3 + 3 HCl = AlCl3 + 3 H2O
Kryger [21]

Answer:

1) 1.235 g.

2) 0.61 g.

Explanation:

  • From the balanced equation:

<em>Al(OH)₃ + 3HCl → AlCl₃ + 3H₂O.</em>

1.0 mol of Al(OH)₃ reacts with 3.0 moles of HCl to produce 1.0 mol of AlCl₃ and 3.0 moles of H₂O.

<em>1) How many grams of HCl can a tablet with 0.880 g of Al(OH)₃ consume? </em>

  • To calculate the amount of HCl needed to consume 0.880 g of Al(OH)₃, we need to calculate the no. of moles of Al(OH)₃:

no. of moles of Al(OH)₃ = mass/molar mass = (0.880 g)/(78.0 g/mol) = 1.13 x 10⁻² mol.

∵ Every 1.0 mol of Al(OH)₃ needs 3.0 moles of HCl to be consumed.

∴ 1.13 x 10⁻² mol of Al(OH)₃ needs (3 x 1.13 x 10⁻² = 3.385 x 10⁻² mol) of HCl.

The no. of grams of HCl = no. of moles of HCl x molar mass of HCl = (3.385 x 10⁻² mol)(36.5 g/mol) = 1.235 g.

<em>2) How much H₂O?</em>

∵ Every 1.0 mol of Al(OH)₃ produces 3.0 moles of H₂O.

∴ 1.13 x 10⁻² mol of Al(OH)₃ produces (3 x 1.13 x 10⁻² = 3.385 x 10⁻² mol) of H₂O.

<em>The no. of grams of H₂O = no. of moles of H₂O x molar mass of H₂O </em>= (3.385 x 10⁻² mol)(18.0 g/mol) = <em>0.6092 g ≅ 0.61 g.</em>

7 0
3 years ago
Other questions:
  • A _ is a device that allows a car to use hydrogen gas to operate.
    8·2 answers
  • A solution is prepared by dissolving 33.0 milligrams of sodium chloride in 1000. L of water. Assume a final volume of 1000. lite
    7·1 answer
  • What is the force exerted by the load being lifted is called?
    14·1 answer
  • Which of the following atoms forms an ionic bond with a sulfur atom?
    7·1 answer
  • The decomposition of NI3 to form N2 and I2 releases −290.0 kJ of energy. The reaction can be represented as 2NI3(s)→N2(g)+3I2(g)
    13·1 answer
  • How many milliliters of 2.5 M HCl are required<br> to exactly neutralize 1.5 L of 5.0 M NaOH?
    13·1 answer
  • PLEASEEEE HELPPP ME WITH THISS
    8·1 answer
  • A greater force is required to move an object with a larger mass than one with a smaller<br> mass.
    13·2 answers
  • How do i find the name of an element
    7·2 answers
  • Which describe beta decay? check all that apply. in beta decay, a proton becomes a neutron and a positron. in beta decay, a neut
    6·1 answer
Add answer
Login
Not registered? Fast signup
Signup
Login Signup
Ask question!