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
djyliett [7]
3 years ago
12

Uranium–232 has a half–life of 68.9 years. A sample from 206.7 years ago contains 1.40 g of uranium–232. How much uranium was or

iginally present?
Chemistry
2 answers:
Mnenie [13.5K]3 years ago
7 0

it's 11.2, other guy prob made a typo is all

givi [52]3 years ago
4 0

<u>Answer:</u> The initial amount of Uranium-232 present is 11.3 grams.

<u>Explanation:</u>

All the radioactive reactions follows first order kinetics.

The equation used to calculate half life for first order kinetics:

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

We are given:

t_{1/2}=68.9yrs

Putting values in above equation, we get:

k=\frac{0.693}{68.9}=0.0101yr^{-1}

Rate law expression for first order kinetics is given by the equation:

k=\frac{2.303}{t}\log\frac{[A_o]}{[A]}

where,

k = rate constant = 0.0101yr^{-1}

t = time taken for decay process = 206.7 yrs

[A_o] = initial amount of the reactant = ?

[A] = amount left after decay process = 1.40 g

Putting values in above equation, we get:

0.0101yr^{-1}=\frac{2.303}{206.7yrs}\log\frac{[A_o]}{1.40}

[A_o]=11.3g

Hence, the initial amount of Uranium-232 present is 11.3 grams.

You might be interested in
In a study of the following reaction at 1200 K it was observed that when the equilibrium partial pressure of water vapor is 15.0
sp2606 [1]

Answer:

The value of K_p for this reaction at 1200 K is 4.066.

Explanation:

Partial pressure of water vapor at equilibrium = p^o_{H_2O}=15.0 Torr

Partial pressure of hydrogen gas at equilibrium = p^o_{H_2}=?

Total pressure of the system at equilibrium P = 36.3 Torr

Applying Dalton's law of partial pressure to determine the partial pressure of hydrogen gas at equilibrium:

P=p^o_{H_2O}+p^o_{H_2}

p^o_{H_2}=P-p^o_{H_2O}=36.3 Torr- 15.0 Torr = 21.3 Torr

3 Fe(s) 4 H_2O(g)\rightleftharpoons Fe_3O_4(s) 4 H_2(g)

The expression of K_p is given by:

K_p=\frac{(p^o_{H_2})^4}{(p^o_{H_2O})^4}

K_p=\frac{(21.3 Torr)^4}{(15.0 Torr)^4}=4.066

The value of K_p for this reaction at 1200 K is 4.066.

6 0
3 years ago
Mole are in 5.1 grams of beryllium ?
chubhunter [2.5K]
5.1/9.01 ≈ 0.566 moles
7 0
3 years ago
¿Que es el codigo genetico?
Burka [1]

Answer:

Los tripletes de nucleótidos de las moléculas de ADN y ARN que transportan información genética en las células vivas.

Explanation:

5 0
3 years ago
. Which of the following do low pressures not produce?
aleksley [76]

Answer:

the question is incomplete

3 0
3 years ago
Create the Lewis structure of CF4. NOTE: do only the step asked for in each part and then click Check–don't work ahead to solve
Naya [18.7K]

To create the Lewis structure we need to take into account the octet rule: atoms tend to gain, lose or share electrons to complete their valence shell with 8 electrons.

C belongs to Group 4A in the periodic table so it has 4 valence electrons. It needs to share 4 pairs of electrons to complete the octet.

F belongs to Group 7A in the periodic table so it has 7 valence electrons. Each F needs to share 1 pair of electrons to complete the octet.

As a consequence, in CF₄, C will form a single bond with each F and all the octets will be complete.

5 0
3 years ago
Other questions:
  • Write the balanced nuclear equation for alpha decay of polonium−218. include both the mass numbers and the atomic numbers with e
    12·1 answer
  • How do decomposers get energy?
    11·1 answer
  • C2H5OH is able to dissociate in water to conduct an electric current. This compound could be classified as
    9·1 answer
  • Convert the boiling temperature at gold, 2966 degree centigrate , into degrees fahrenheit and kelvin.
    7·1 answer
  • Organisms with traits that are well-suited to an environment tend to survive and reproduce at a greater rate than organisms that
    8·1 answer
  • What is the systematic name of NH4ClO3
    12·1 answer
  • What is past form of be<br>​
    10·2 answers
  • Combination reactions always:
    13·1 answer
  • What is einsteins theory of relativity?
    9·1 answer
  • What are three ways invasive species can be introduced into an environment?
    7·1 answer
Add answer
Login
Not registered? Fast signup
Signup
Login Signup
Ask question!