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
ExtremeBDS [4]
4 years ago
6

The radioisotope sodium-24 is used to determine the levels of electrolytes in the body. A 16-μg sample of sodium-24 decays to 2.

0 μg in 45 h. What is the half-life, in hours, of sodium-24?
Chemistry
1 answer:
mario62 [17]4 years ago
8 0

Answer:

t = 15 hours

Explanation:

To get this, we need to write the general expression for the mass or concentration in life decay which is the following:

A = Ao * e^(-kt)   (1)

K is a constant decay and depends of the half life. The expression is:

k = ln2 / t₁/₂   (2)

In this question, we have the innitial mass and the final mass, and the time required to get that mass. So, with these data, we first solve for the constant k, and then, use this value to get the half life. In other words, we solve for k in (1) and then, solve for half life in (2):

2 = 16 * e(-45k)

2/16 = e(-45k)

0.125 = e(-45k)

ln(0.125) = -45k

k = -ln(0.125)/45

k = 0.0462 h⁻¹

Now that we have k, let's calculate half life:

t₁/₂ = ln2/k

t₁/₂ = ln2 / 0.0462

t₁/₂ = 15 h

This is the half life of sodium-24

You might be interested in
What is the main function of the cell membrane in an animal cell?
Paladinen [302]

Answer:

A cell's plasma membrane, also known as the cell membrane, provides protection. It also maintains a constant atmosphere within the cell, and the membrane serves a variety of purposes. The first is to transport nutrients into the cell, and the second is to transport toxic compounds out

Explanation:

5 0
3 years ago
Read 2 more answers
which state of matter is made up of atoms and molecules that are held closely together by attractive forces between them
Amiraneli [1.4K]

Answer:

In solid state all the atoms and molecules are held very closely together by strong attractive forces.

Explanation:

Solids have definite volume and shape.

In solids molecules are tightly pack and very close to each other.

Their melting and boiling point are every high.

The densities of solids are also very high as compared to the liquid and gas.

There are very strong inter molecular forces are present between solid molecules.

Consider the example of water. Which is present in three state solid, liquid and gas. In the form of ice its volume is less as compared to the liquid and gas, because molecules are tightly packed. If we melt the same ice we observe the volume is increase because molecules are now apart from each other. The distance between the molecules of water increased. If the same amount of water is evaporated the molecule of water will occupy all available space , and the distance between the water molecules get increased and inter molecular forces becomes negligible.

8 0
3 years ago
A salt derived from a weak base and a strong acid will yield what kind of salt?
lara31 [8.8K]
A salt derived from a weak base and a strong acid will yield an acid salt
5 0
3 years ago
Emperical formula of carbon dioxide
Stells [14]

CO2 is the emperical formula of carbon dioxide

6 0
3 years ago
Read 2 more answers
What volume of 0.500 m h2so4 is needed to react completely with 20.0 ml of 0.400 m lioh?
ExtremeBDS [4]
The balanced chemical equation for the above reaction is as follows;
2LiOH + H₂SO₄ ---> Li₂SO₄ + 2H₂O
stoichiometry of base to acid is 2:1
Number of OH⁻ moles reacted = number of H⁺ moles reacted at neutralisation
Number of LiOH moles reacted = 0.400 M / 1000 mL/L x 20.0 mL = 0.008 mol 
number of H₂SO₄ moles reacted - 0.008 mol /2 = 0.004 mol 
Number of H₂SO₄ moles in 1 L - 0.500 M
This means that 0.500 mol  in 1 L solution 
Therefore 0.004 mol in - 1/0.500 x 0.004 = 0.008 L 
therefore volume of acid required = 8 mL 
4 0
3 years ago
Other questions:
  • Smog usually forms from gound-level ozone and what other human-made pollutant?
    10·2 answers
  • What is Heterogeneous? And an example. What is Homogeneous? And an example. I just need those, thanks
    5·1 answer
  • Which statement is true for the highest point of a projectile trajectory?
    10·2 answers
  • 6. a) Why is isocyanic acid prepared ""in situ"" in the Dulcin experiment? [2 pts] b) Draw a plausible Lewis structure for isocy
    15·1 answer
  • Which combustion equation violates the law of conservation of matter? A) CH4 + 2O2 -> CO2 + 2H2O B) C3H8 + 6O2 -> 3CO2 + 4
    5·2 answers
  • The prefix himbo-means heap : true false
    6·1 answer
  • Why do chemical properties change?
    15·1 answer
  • Identify the type of the bond​
    13·1 answer
  • Atoms and molecules sbr2
    10·1 answer
  • Why Ethyl amine is more basic than aniline​?
    10·1 answer
Add answer
Login
Not registered? Fast signup
Signup
Login Signup
Ask question!