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
lesantik [10]
2 years ago
9

A sample of radioactive waste has a half-live of 40 years and an activity level of 4 curies. After how many years will the activ

ity level of this sample be 0. 5 curies?
Chemistry
1 answer:
Westkost [7]2 years ago
8 0

After 160 years, the activity level of the sample will be 0.5 curies.

<h3>What is half-life?</h3>

Half life of any radioactive waste is the half decay of that product.

The formula is \dfrac{\lambda }{\lambda_1} = 2^\dfrac{a}{b}

Where, λ is 4 cruies

λ1 is 0.5 cruies

b = 40 years

Putting the values in the equation

\dfrac{4}{0.5} = 2^\dfrac{a}{40}\\\\\\\dfrac{a}{40} =  4\\ = 160 years

Thus, the correct option is 160 years.

Learn more about half-life

brainly.com/question/24710827

#SPJ4

You might be interested in
Hhhhhhhhhhhhhhhhhhhhhhhhheeeeeeeeeelpppppppppppp
4vir4ik [10]

Answer:

- Producers are organisms that make their own food. - They are autotrophs. - They can convert inorganic substances into organic substances. ... - Consumers are organisms that need to eat other organisms to obtain energy.

Explanation:

3 0
3 years ago
A block of iron has a mass of 826 g. What is the volume of the block of iron whose density at 25°C is 7.9 ?
kolezko [41]

Answer:

104.56cm³

Explanation:

Mass=826g

Density =7.9g/cm³

Volume =Mass /Density

Volume =826/7.9

Volume =104.56cm³

5 0
2 years ago
Using the systematic approach for equilibrium problems, calculate the pH of 0.05 M HOCl. Ka= 3.0*10-8 Group of answer choices 3.
SVEN [57.7K]

Answer:

The pH is equal to 4.41

Explanation:

Since HClO is a weak acid, its dissociation in aqueous medium is:

                HClO   ⇄   ClO-  +  H+

start:          0.05            0         0

change       -x               +x       +x

balance     0.05-x         x         x

As it is a weak acid it dissociates very little, in its ClO- and H + ions, so the change is negative, where x is a degree of dissociation.

the acidity constant when equilibrium is reached is equal to:

Ka=\frac{[ClO-]*[H+]}{[HClO]}=\frac{x*x}{0.05-x}=3x10^{-8}

The 0.05-x fraction can be approximated to 0.05, because the ionized fraction (x) is very small, therefore we have:

3x10^{-8}=\frac{x^{2} }{0.05}

clearing the x and calculating its value we have:

x=3.87x10^{-5}=[H+]=[ClO-]

the pH can be calculated by:

pH=-log[H+]=-log[3.87x10^{-5}]=4.41

7 0
3 years ago
Which of the following are examples of electromagnetic waves?
liubo4ka [24]

Answer:

C

Explanation:

Electromagnetic waves travel at the speed of light and do not require molecules (gas, solid or liquid) to vibrate and travel.

Soundwaves when singing or from thunder vibrate particles to reach our ears and are known as mechanical waves.

8 0
3 years ago
Which of the following statements is not an accurate description of a factor that contributes to the ordering of the spectrochem
MArishka [77]

Answer:

Higher oxidation state metals form stronger bong with ligands

Explanation:

Ligand strength are based on oxidation number, group and its properties

5 0
3 years ago
Other questions:
  • What is the index of hydrogen deficiency of a compound with a molecular formula of c6h15n?
    7·1 answer
  • 0.1005 liters is the same as: A. 0.0001005 cm3 B.0.1005 cm3 C.100.5 cm3 D.0.01005 cm3 and A. 0.01005 mL B. 0.1005 mL C. 0.000100
    10·2 answers
  • An empty beaker weighs 32.4257 grams. A 10 ml pipet sample of an unknown liquid is
    5·1 answer
  • which of the following ions is formed when the positive hydrogen ions from an acid bond to water molecules? H- OH- H2O+ H3O+
    12·2 answers
  • What is density? what does it tell you about substance?
    10·1 answer
  • One electron has a mass of<br> 1 amu<br> 2 amu<br> 0 amu<br> 3 amu
    13·1 answer
  • Please answer the question for me and show proof i will mark brainliest than you!
    9·1 answer
  • What is the coefficient of H2O when the following equation is properly balanced with the smallest set of whole numbers?
    15·2 answers
  • FILL IN THE BLANK! ILL GIVE BRAINLIEST The heat trapping nature of__and other gases was demonstrated in the mid 19th century
    8·1 answer
  • Describe two or three ways in which the measurements you made could lead to errors in the results. Explain how each error would
    12·1 answer
Add answer
Login
Not registered? Fast signup
Signup
Login Signup
Ask question!