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
Furkat [3]
3 years ago
9

What would the percentage of thorium-232 (parent compound) be in a rock that was dated at 2.8 billions years?

Chemistry
1 answer:
just olya [345]3 years ago
5 0

The half-life of Th-232 is 1.405 × 10¹⁰ years  

Time elapsed = 2.8 x 10⁹ years  

Equation of radioactive decay:

A = A₀ = (1/2)^ t/t₁/₂

where A₀ is the initial amount, A is the amount after time t, t₁/₂ is the half file

The fraction of thorium-232 that remains in the rock after 2.8 billions years is,

A/A₀ = (1/2) ^ (2.8 x 10⁹/ 1.405 × 10¹⁰) = 0.871

Therefore, the percentage of thorium-232 in the rock that was dated at 2.8 billions year = 87.1%


You might be interested in
What compound is composed of 3 fatty acids and glycerol?
Nikolay [14]
Triglyceride/fats
weeeeeee
8 0
2 years ago
Which type of bond will most likely be found in hbr?
Komok [63]
To know that compare the electronegativitis of the two elements.

The electronegativity of H is 2.2
The electronegativity of Br is 2.96

The difference does not seem enough to cause ionic bond. Then it is most likely thaty they form a polar covalent bond.
6 0
3 years ago
Read 2 more answers
Please help ill give you brainiest
Makovka662 [10]

Answer:

c

Explanation:

7 0
2 years ago
Ammonia gas combines with excess oxygen gas to produce nitric oxide and water. How many grams of ammonia gas would have to react
Sedbober [7]

Answer:

11.6g of NH₃(g) have to react

Explanation:

For the reaction:

4 NH₃(g) + 5 O₂(g) → 4 NO(g) + 6 H₂O(g) ΔH = -905kJ

<em>4 moles of ammonia produce 905kJ</em>

Thus, if you want to produce 154kJ of energy you need:

154kJ × (4 mol NH₃ / 905kJ) = <em>0.681moles of NH₃. </em>In mass -Molar mass ammonia is 17.031g/mol-

0.681mol NH₃ × (17.031g / mol) = <em>11.6g of NH₃(g) have to react</em>

3 0
2 years ago
whg doe sthe transfer of electrons from magnesium to oxygen cause the ions produced to attract eachother
almond37 [142]
Oxygen gains two electrons when it bonds to form a complete outer shell and magnesium loses two electrons when bonding to gain its full outer shell. 

As electrons are negative, the oxygen (which gains electrons) will become negative and the magnesium (which loses electrons) will become positive.

The negative and positive ions will then attract to one another due to the magnetic pull of the positive and negative.
8 0
3 years ago
Other questions:
  • Who studied cell reproduction
    15·2 answers
  • Water's _____ property creates positive and negative ions, which are essential for chemical reactions.
    10·2 answers
  • What process form glaciers?
    10·2 answers
  • The Nusselt number is defined as Nu = _____ where Lc is the characteristic length of the surface, h is the convective heat trans
    11·1 answer
  • What conditions must exist for a polyatomic molecule to be nonpolar?
    13·1 answer
  • URGENT!!!!???! Please respond in less than 5 minutes!??!
    9·1 answer
  • A mug is filled with coffee. Which property is an intensive property of the coffee in the mugg
    6·1 answer
  • What is the fancy psychological term for "mental process"?
    7·1 answer
  • Need help with this.
    8·2 answers
  • What is an advantage of using an energy pyramid to describe the flow of energy in an ecosystem?
    14·1 answer
Add answer
Login
Not registered? Fast signup
Signup
Login Signup
Ask question!