answer.
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
yan [13]
2 years ago
5

The isotope 64Cu has t1/2 of 12.7 hours. If the initial concentration of this isotope in an aqueous solution is 845 ppm, what wi

ll the abundance be after 4.00 hours? To solve this problem, first use equation (7) to determine k for 64Cu; then use this k value in equation (6) to obtain the amount of 64Cu, A, remaining after 4.00 hours if the amount present at the start, A0, is 845 ppm.
Chemistry
1 answer:
Kisachek [45]2 years ago
7 0

Answer:

A = 679.2955 ppm

Explanation:

In this case, we already know that 64Cu has a half life of 12.7 hours. The expression to use to calculate the remaining solution is:

A = A₀ e^-kt

This is the expression to use. We have time, A₀, but we do not have k. This value is calculated with the following expression:

k = ln2 / t₁/₂

Replacing the given data we have:

k = ln2 / 12.7

k = 0.0546

Now, let's get the concentration of Cu:

A = 845 e^(-0.0546*4)

A = 845 e^(-0.2183)

A = 845 * 0.8039

A = 679.2955 ppm

This would be the concentration after 4 hours

You might be interested in
When uranium-235 atoms undergo fission, ________ is/are produced?
elena-s [515]
Smaller atoms ; free neutrons and energy
8 0
2 years ago
Suppose you are titrating vinegar, which is an acetic acid solution of unknown strength, with a sodium hydroxide solution accord
Marina CMI [18]

Answer:

M_{acid}=0.563M

Explanation:

Hello there!

In this case, given the neutralization of the acetic acid as a weak one with sodium hydroxide as a strong base, we can see how the moles of the both of them are the same at the equivalence point; thus, it is possible to write:

M_{acid}V_{acid}=M_{base}V_{base}

Thus, we solve for the molarity of the acid to obtain:

M_{acid}=\frac{M_{base}V_{base}}{V_{acid}} \\\\ M_{acid}=\frac{33.98mL*0.1656M}{10.0mL}\\\\ M_{acid}=0.563M

Regards!

5 0
2 years ago
At higher elevations, the boiling point of water decreases, due to the decrease in atmospheric pressure. As a result, what could
amid [387]
When we say decrease in boiling point, that means, we achieve boiling at a more lower temperature (lower than 100deg C). This is due to the lower atmospheric pressure. Boiling happens when the vapor pressure is equal the atmospheric pressure. Lower atmospheric pressure takes lower temperature for vapor pressure to equate with the atmospheric pressure. The answer here is letter B. 
At higher elevations, it would take longer to hard boil an egg, because there is a lower boiling point, so the egg is boiling in water at a lower temperature.

8 0
2 years ago
How many moles of chromium(iii) nitrate are produced when chromium reacts with 0.85 moles of lead(iv) nitrate to produce chromiu
Alexxandr [17]
The  moles  of  chromium (iii)  nitrate  produced  is  calculated  as   follows

write  the  equation  for  reaction

 3  Pb(NO3)2  +  2 Cr  =  2 Cr(NO3)3  +  3  Pb

by  use  of  mole  ratio  between  Pb(NO3)2  to  Cr(NO3)3  which  is  3  :  2  the  moles  of  Cr(NO3)3  is therefore  
=  0.85  x2  /3  =  0.57   moles
5 0
2 years ago
The first ionization energy, e, of a potassium atom is 0.696 aj. what is the wavelength of light, in nm, that is just sufficient
elena55 [62]
The formula to be used for this problem is as follows:

E = hc/λ, where h is the Planck's constant, c is the speed of light and λ is the wavelength. Also 1 aJ = 10⁻¹⁸ J

0.696×10⁻¹⁸ = (6.62607004×10⁻³⁴ m²·kg/s)(3×10⁸ m/s)/λ
Solving for λ,
λ = 2.656×10⁻⁷ m or <em>0.022656 nm</em>
6 0
2 years ago
Other questions:
  • How many grams are in 2.5 pound sample
    14·1 answer
  • List the following compounds in decreasing electronegativity difference. cl2 hcl nacl
    13·1 answer
  • Dehydrohalogenation of tert-pentyl bromide at higher temperatures will produce 2-methyl-1-butene as the chief product when
    12·1 answer
  • 6. Find the number of centimeters in 1.00 x 102 yards. (1 yd = 3 ft, 1 ft = 12 in, 2.54 cm = 1
    5·1 answer
  • a weather balloon is filled with 200L of helium at 27 degree Celsius and 0.950 atm. What would be the volume of the gas at -10 d
    6·1 answer
  • N a football game, two players tackle each other so hard that they both fly in opposite directions after they hit each other. �W
    10·1 answer
  • Sodium carbonate (Na2CO3) is available in very pure form and can be used to standardize acid solutions. What is the molarity of
    10·1 answer
  • What is the melting point of a 3L aqueous solution that contains 100g of MgCl2? kf H2O=1.86 rhoH2O=1gmL
    12·2 answers
  • Water at the bottom of a narrow metal tube is held at a constant temperature of 293 K. The total pressure of air (assumed dry) i
    13·1 answer
  • A change in the state of matter is caused if enough _____ is added to or removed from an object.​
    13·1 answer
Add answer
Login
Not registered? Fast signup
Signup
Login Signup
Ask question!