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
bearhunter [10]
3 years ago
13

For a reaction: aA → Products, [A]o -4.3 M, and the first two half-lives are 56 and 28 minutes, respectively. Calculate k (witho

ut units). Show Work!
A. 7.7 x 10^-2
B. 4.2 x 10^-3
C. 3.8 x 10^-2
D. 8.3 x 10^-3
E. None of these​
Chemistry
1 answer:
Mkey [24]3 years ago
4 0

Answer:

C.3.8\times 10^{-2}

Explanation:

We are given that

Initial concentration, [A]_o=4.3 M

First half life, t_{\frac{1}{2}}=56minutes

Second half life, t'_{\frac{1}{2}}=28minutes

We have to find K.

The given reaction is zero order reaction.

We know that for zero order reaction

t_{\frac{1}{2}}=\frac{[A]_o}{2k}

Using the formula

56=\frac{4.3}{2k}

k=\frac{4.3}{2\times 56}

k=3.8\times 10^{-2}

Hence, option C is correct.

You might be interested in
Which of the following is one part of a chemical formula?
melomori [17]

Answer:

C

Explanation:

You would be correct in guessing C as in a chemical formula symbol of each element is stated.

Like Salt is Sodium Chloride, and its chemical formula is NaCl (Na=sodium, Cl= chloride)

7 0
3 years ago
What is the change in density if a sample goes from 3.21 g/L to 5.43 g/mL?
Step2247 [10]

Answer:

\Delta \rho =2.22 g/mL

Explanation:

Hello,

In this case, since a change in science is widely known to be considered as a subtraction between the the final and initial values of two measured variables and is represented via Δ, here the final density is 5.43 g/mL and the initial one was 3.21 g/mL, therefore, the change in density is:

\Delta \rho=\rho _f-\rho _i\\ \\\Delta \rho=5.43g/mL-3.21g/mL\\\\\Delta \rho =2.22 g/mL

Best regards.

3 0
3 years ago
Which of these is the final result of secondadry succession?
Grace [21]

Answer:

a

Explanation:

ADAPTATIOnn but if thhere would be an option o all the above it would be that

5 0
3 years ago
Read 2 more answers
It is logical to conclude that water cannot dissolve vegetable oil because the oil is
Gekata [30.6K]
In chemistry, there is a common note that says, "Like dissolves like".

This pertains to the concept that polar substances can dissolve only other polar substances. Also, nonpolar substances are also only able to dissolve nonpolar substances. 

Polarity of the substance depends primarily on the type of bond and the difference in electronegativity. 

Water is a polar substance while vegetable oil is not. From the concept presented above, it may be concluded that water will not be able to dissolve the vegetable oil and the assumption is logical. 
3 0
3 years ago
Read 2 more answers
If 15.0 mL of phosphoric acid completely neutralizes 38.5 mL of 0.150 mol/L calcium hydroxide, what is the concentration of the
Sedbober [7]

Answer:

Let me give it a try.

H3PO4 + Ca(OH)2 = Ca3(PO4)2 + H2O

Balancing this reaction

2H3PO4 + 3Ca(OH)2 == Ca3(PO4)2 + 6H2O.

Moles= Molarity x Volume

Volume = 38.5ml = 0.0385L

Moles of Ca hydroxide = 0.150m/L x 0.0385L

(Notice the units canceling out...leaving moles).

=0.005775moles of Ca(OH)2.

From balanced reaction...

3moles of Ca(OH)2 completely reacts with 2moles of H3PO4

0.005775moles of Ca(OH)2 would completely react with....

= 0.005775 x 2/(3)

=0.00385moles of H3PO4.

Now we're looking for its Concentration in Mol/L

Molarity=Moles of solute/Volume of solution(in L)

Volume of solution assuming no other additions to the reaction = 15ml + 38.5ml =53.5ml =0.0535L

Molarity = 0.00385/0.0535

=0.072Mol/L.

If this is wrong

then Simply Try The formula for Mixing of solutions

C1V1 = C2V2

0.15 x 38.5 = C2 x (15+38.5)

C2 = 0.11M/L.

7 0
3 years ago
Other questions:
  • You are given two aqueous solutions with different ionic solutes (Solution A and Solution B). What if you are told that Solution
    6·1 answer
  • Explain the similarities and differences between a 1M solution of NaOH and a 1m solution of NaOH
    14·1 answer
  • In an unconformity between two layers of rock, how is the lower layer usually described?
    15·2 answers
  • Help with chemistry
    14·1 answer
  • What is the angle between the carbon-sulfur bonds in the carbon disulfide ( cs2 ) molecule?
    9·1 answer
  • Solutions of sulfuric acid and lead(ll) acetate react to form solid lead(ll) sulfate and a solution of acetic acid. If 7.50 g of
    11·1 answer
  • What is the solution to the problem expressed to the correct number of significant figures?
    8·1 answer
  • Warm Up
    12·2 answers
  • 14. As the temperature of a gas in a closed container increasses, what is true of the particles in the substance? (2 points)
    11·1 answer
  • Iwsk3eidwujfdujeudcwix vvfedsxdwsx
    10·2 answers
Add answer
Login
Not registered? Fast signup
Signup
Login Signup
Ask question!