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
m_a_m_a [10]
3 years ago
8

After 11.5 days, 12.5% of a sample of radon-222 that originally weighed 42g remains. What is the half-life of this isotope?

Chemistry
1 answer:
Bond [772]3 years ago
5 0
Half-life is defined as the amount of time it takes a given quantity to decrease to half of its initial value.  The equation to describe the decay is
Nt=N0(1/2) ^{t/t(1/2)}  where N0 is the initial quantity, Nt is the remaining quantity after time t, t1/2 is the half-time.  So work out the equation, t1/2 = t (-ln2)/ln(Nt/N0) = 11.5*(-ln2)/ln(12.5/100) = 3.83 days
You might be interested in
Explain the concept of electron density
Doss [256]
Electron density is the measure of theprobability of an electron being present at a specific location.

In molecules, regions of electron density are usually found around the atom, and its bonds. In de-localized orconjugated systems, such as phenol,benzene and compounds such as hemoglobin and chlorophyll, the electron density covers an entire region, i.e., in benzene they are found above and below the planar ring. This is sometimes shown diagrammatically as a series of alternating single and double bonds. In the case of phenol and benzene, a circle inside a hexagon shows the de-localized nature of the compound.

5 0
3 years ago
I need a person i can love and not get hurt
Katyanochek1 [597]

Answer:

You'll find someone. There's a someone for everyone.

Explanation:

And I know how you feel.

7 0
3 years ago
Question 9 (5 points)
frozen [14]

Answer:

A. air pressure,this is answer.

5 0
2 years ago
Read 2 more answers
What type of particles move to create electricity
yKpoI14uk [10]

Answer:

Electrons

Explanation:

6 0
3 years ago
Read 2 more answers
Giving brainless to who gets it correct
mafiozo [28]
1-energy
2- force
3- force
4- force
5- energy
6- energy
5 0
2 years ago
Other questions:
  • In the following reaction, what is the relationship between the rate at which the nitrous oxide is used up, the rate at which th
    15·1 answer
  • Question 9
    5·1 answer
  • Which of these is not true of Bohr's model of the atom ?
    11·2 answers
  • Which of the following happens during a new moon? More than half of the moon is visible from Earth. Less than half of the moon i
    14·1 answer
  • What is the pH of a 6.4x10^-10 m OH- solutions
    7·1 answer
  • Pls i need this for finals and fast
    5·1 answer
  • Which hypothesis is testable using a scientific experiment? O A. Ancient people liked iron tools better than copper tools. O B.
    5·1 answer
  • How can the Swartz process be modified to work for bacteria?​
    15·1 answer
  • What are Chemical Calculations ?​
    7·2 answers
  • 1. When conducting this experiment, some procedures call for heating the substance several times and recording the mass after ea
    6·1 answer
Add answer
Login
Not registered? Fast signup
Signup
Login Signup
Ask question!