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
WITCHER [35]
3 years ago
12

If the amount of radioactive sodium-24, used for studies of electrolytes within the body, in a sample decreases from 0.8 to 0.2

mg in 30.0 h , what is the half-life of sodium-24?
Chemistry
1 answer:
kirill [66]3 years ago
6 0

Answer:

15 h

Explanation:

Okay, the first thing that we all have to know before we can answer this question is that this Topic that is, Chemistry of Radioactivity is related to kinetics in a way that Radioactive disintegration follows the first order of Reaction which is under kinetics. So, we will be using the first order kinetics rate law to answer this question. Using the equation (1) below;

k =[ 2.303/ t ]×log ([N°}/ [Nr]) --------(1).

We are given from the question that N° = initial sample = 0.8 mg and Nr= sample remaining = 0.2 and the time taken = t= 30.0 h.

k= (2.303/ 30.0 h ) × log (0.8/0.2).

k=0.076768 h^-1 × log (4).

k= 0.076768 h^-1 × 0.6021.

k= 0.0462 h^-1.

Therefore, using the formula for Calculating half life below for first order kinetics we will be able to find out answer.

k = ln 2/ t(1/2). Where t(1/2) is the half life.

t(1/2) = ln 2/ k.

t(1/2) = ln 2 / 0.0462 h^-1.

t(1/2)= 0.6931/0.0462 h^-1.

t(1/2)=15 h

You might be interested in
When a hurricane approaches land, people living directly on the
Tatiana [17]

Answer:

True

Explanation:

When a hurricane is dangerous enough that authorities say to evacuate, you should for your own safety.

3 0
3 years ago
Find the number of moles of butane (c4h10) in 21g sample of butane gas​
iogann1982 [59]

Answer:

0.362 moles

Explanation:

Mass of butane = 21g

Molar mass of carbon = 12g / mol

Molar mass of hydrogen = 1g/mol

Molar mass of butane ? = [(12*4) * (1*10)]

Molar mass of butane = 58g / mole

Number of moles = mass of molecules / molar mass of molecule

Number of moles = 21 / 58

Number of moles of butane = 0.362 moles

The number of moles in 21g of butane is 0.362 moles

8 0
3 years ago
Question 5 (1 point)
mart [117]

Answer:

hhhheeelllpppp

Explanation:

i need this answer tooooo

3 0
3 years ago
Read 2 more answers
Question 4 4. Rubber, oxygen and paper are all made up of A. atoms B. chlorine C. carbon D. animal cells Question 5​
777dan777 [17]
A. atoms because they are all matter and matter is made up of atoms
8 0
3 years ago
True or false table salt NaC1 is a molecular compound
ANTONII [103]

Answer:

If you mean NaCl is table salt than true

but if you mean NaC1 than false

Explanation:

5 0
3 years ago
Other questions:
  • The products obtained by cracking an alkane, X, are methane, ethene and propene. The mole fraction of ethene in the products is
    12·1 answer
  • Why would you classify hydrogen as a nonmetal 2017?
    7·2 answers
  • For an endothermic reaction, how will the value for Keq change when the temperature is increased?
    12·2 answers
  • What is a well-mixed mixture that contains a solvent and at least one solute
    14·1 answer
  • (04.02 MC)
    5·1 answer
  • Why has JET not been able to get fusion reactions to work?
    13·1 answer
  • When compounds form, which of the following statements is true about the elements that form them?
    7·1 answer
  • Do you have any ideas for a sodium poster project other than a salt shaker?
    7·1 answer
  • A medium that works by showing two reaction types, such as a color change in some colonies but not in others is called a(n)
    6·1 answer
  • The remnants of an ancient fire in a cave in Peru showed a decay rate of 8.0 counts per minute per gram of carbon. Assuming that
    9·1 answer
Add answer
Login
Not registered? Fast signup
Signup
Login Signup
Ask question!