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
Kipish [7]
2 years ago
5

If the half life of iridium-182 is 15 years, how much of a 3 gram sample is left after 2 half-lives?

Chemistry
1 answer:
padilas [110]2 years ago
4 0

Answer:

D. 0.75 grams

Explanation:

The data given on the iridium 182 are;

The half life of the iridium 182, t_{(1/2)} = 15 years

The mass of the sample of iridium, N₀ = 3 grams

The amount left, N(t) after two half lives is given as follows;

N(t) = N_0 \left (\dfrac{1}{2} \right )^{\dfrac{t}{t_{1/2}} }

For two half lives, t = 2 × t_{(1/2)}

∴ t = 2 × 15 = 30

\dfrac{t}{t_{(1/2)}} = \dfrac{30}{15} = 2

\therefore N(t) = 3 \times\left (\dfrac{1}{2} \right )^2 = 0.75

∴ The amount left, N(t) = 0.75 grams

You might be interested in
Which carbon reservoirs are underutilized
statuscvo [17]
Carbon is stored in the ocean
8 0
3 years ago
A gas system has an initial number of moles of 0.693 moles with the volume unknown. When the number of moles changes to 0.928 mo
lara [203]

Answer:

The initial volume in mL is 5959.2 mL

Explanation:

As the number of moles of a gas increases, the volume also increases.  Hence, number of moles and volumes are directly proportional i.e

n ∝ V

Where n is the number of moles and V is the volume

Then, n = cV

c is the proportionality constant

∴n/V = c

Hence n₁/V₁ = n₂/V₂

Where n₁ is the initial number of moles

V₁ is the initial volume

n₂ is the final number of moles

and V₂ is the final volume.

From the question,

n₁ = 0.693 moles

V₁ = ?

n₂ = 0.928 moles

V₂ = 7.98 L

Putting the values into the equation

n₁/V₁ = n₂/V₂

0.693 / V₁ = 0.928 / 7.98

Cross multiply

∴ 0.928V₁ = 0.693 × 7.98  

0.928V₁ = 5.53014

V₁ = 5.53014/0.928

V₁ = 5.9592 L

To convert to mL, multiply by 1000

∴ V₁ = 5.9592 × 1000 mL

V₁ = 5959.2 mL

Hence, the initial volume in mL is 5959.2 mL

5 0
2 years ago
Use this diagram to answer the following
mylen [45]

Answer:An atom

Explanation:

Because  molecules more spread out and have things that connnect them and are not bunched up togoether

And Atoms are all packed up like in the picture

Hope this helps!:D

4 0
2 years ago
What would cause a liquid to turn into a solid?
KIM [24]
It’s C
Cooling a liquid til it freezes will cause a liquid to turn into a solid
3 0
2 years ago
Read 2 more answers
Why are halogens reactive?
erica [24]

<u>Halogens are reactive because:</u>

They have high electronegativity and also high nuclear charge. So, they are reactive and also gain an electron when they react with other elements.

Since they are very reactive, halogens are very harmful to living organisms. Some of the halogens are fluorine, chlorine, bromine, iodine, astatine. These are mostly non metals. Fluorine is one of the most reactive gas and also very toxic gas. When Fluorine reacts with glass along with small amounts of water, it forms silicon tetra fluoride (SiF4). Hence fluorine should be handled with substances like the inert organofluorine compound Teflon.

8 0
2 years ago
Other questions:
  • 20g of sugar is stirred into a beaker containing 100 g of water. After the sugar has completely dissolved, the solution is put o
    6·2 answers
  • Propene. What does the name of this hydrocarbon tell you about it’s molecular structure?
    7·1 answer
  • A barium hydroxide solution is prepared by dissolving 2.06 g of Ba(OH)2 in water to make 32.9 mL of solution. What is the concen
    11·1 answer
  • Gas molecules are constantly in motion.<br><br> True or False?
    9·1 answer
  • Atoms that have the same number of outer electrons...
    9·1 answer
  • A chemist determined by measurements that moles of calcium sulfide participate in a chemical reaction. Calculate the mass of cal
    12·1 answer
  • What statement does not accurately describe the following equation? C6H12O6+---&gt;6H20+6CO2+energy A) oxygen is a react ant B)
    10·2 answers
  • Is the following equation balanced? Why or why not?<br> 2H2 +02 → 2H,0
    12·1 answer
  • What are two social and economical impacts of Mass Movements?
    11·1 answer
  • Where are all metalloid found in this periodic table?
    13·2 answers
Add answer
Login
Not registered? Fast signup
Signup
Login Signup
Ask question!