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
Romashka [77]
3 years ago
11

Sodium-25 was to be used in an experiment, but it took 3.0 minutes to get the sodium from the reactor to the laboratory. If 8.0

mg of sodium-25 was removed from the reactor, how many mg of sodium-25 were placed in the reaction vessel 3.0 minutes later if the half life of sodium-25 is 60 seconds.
Chemistry
1 answer:
Ksenya-84 [330]3 years ago
5 0

Sodium-25 after 3 minutes : 1.0625 mg

<h3>Further explanation</h3>

General formulas used in decay:  

\large{\boxed{\bold{N_t=N_0(\dfrac{1}{2})^{t/t\frac{1}{2} }}}

T = duration of decay  

t 1/2 = half-life  

N₀ = the number of initial radioactive atoms  

Nt = the number of radioactive atoms left after decaying during T time  

<h3 />

No=8 mg

t1/2=60 s

T=3 min=180 s

\tt Nt=No\dfrac{1}{2}^{T/t1/2}\\\\Nt=8.5\dfrac{1}{2}^{180/60}\\\\Nt=8.5(\dfrac{1}{2})^3\\\\Nt=1.0625~mg

You might be interested in
You just got home from a run on a hot Atlanta afternoon. You grab a 1.00 liter bottle of water and drink three quarters of it in
-Dominant- [34]

Answer:

¾ litters of water was consumed

2.24 litters = 1 mole of water

Therefore ¾÷2.24 moles was consumed

0.33 moles

8 0
3 years ago
The average rate of disappearance of ozone in the reaction 2o3(g) → 3o2(g) is found to be 7.25×10–3 atm over a certain interval
worty [1.4K]
<h3><u>Answer</u>;</h3>

1.0875 x 10-2 atm

<h3><u>Explanation;</u></h3>

2O3(g) → 3O2(g)

rate = -(1/2)∆[O3]/∆t = +(1/3)∆[O2)/∆t  

The average rate of disappearance of ozone ... is found to  

be 7.25 × 10–3 atm over a certain interval of time.

This means (ignoring time)

∆[O3]/∆t = -7.25 × 10^–3 atm  

(it is disappearing, thus the negative sign)

rate = -(1/2)∆[O3]/∆t  

rate = -(1/2)*(-7.25 × 10^–3 atm)

      = 3.625 × 10^–3 atm  

Now use the other part of the expression:  

rate = +(1/3)∆[O2)∆t  

3.625 × 10–3 atm = +(1/3)∆[O2)/t  

∆[O2)/∆t = (3)*(3.625× 10^–3 atm)

              = 1.0875 x 10-2 atm over the same time interval

4 0
3 years ago
What type of product is formed when acids are added to some ionic compounds?
Andru [333]

Answer:

<em>Your</em><em> </em><em>Answer</em><em> </em><em>is</em><em> </em><em>Option</em><em> </em><em>A</em><em> </em><em>that</em><em> </em><em>is</em><em> </em><em>Gas</em><em>.</em>

3 0
2 years ago
What is the pressure in mm hg of a 0.025 mole sample of co2 at 350 k in a 200 l container?
Leni [432]

Answer:

0.65mmHg

Explanation:

Take R =8.314J/mol/K

V=200dm3

PV=nRT

P=0.025×8.314×623/200

=0.65mmHg

7 0
1 year ago
What are some ways we can monitor earthquakes ?
a_sh-v [17]

Answer:

Earthquakes are measured using instruments called seismometers, that detect the vibrations caused by seismic waves as they travel through the crust. Also, laser beams can be used

Explanation:

5 0
3 years ago
Other questions:
  • Which chemical weathering process is caused by oxygen and water acting on iron?
    15·1 answer
  • By the end of this lab, you will determine whether you should add cocoa mix (a solid) before or after heating water (liquid) to
    9·2 answers
  • Complete ionic equation with phases<br> CaBr2(aq) + 2AuClO4(aq) → 2AuBr(s) + Ca(ClO4)2(aq)
    11·1 answer
  • Please do question 20 (help)
    9·1 answer
  • How many grams of ethylene glycol (c2h6o2 must be added to 1.25 kg of water to produce a solution that freezes at -5.88 ∘c?
    14·1 answer
  • Why are ethics important when considering experiments??
    8·2 answers
  • What is non lustrous ?
    5·2 answers
  • Use the equation:
    12·1 answer
  • Please help due tomorrow
    5·1 answer
  • 100 Point test please help
    8·1 answer
Add answer
Login
Not registered? Fast signup
Signup
Login Signup
Ask question!