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
pentagon [3]
3 years ago
13

The radioactive isotope of lead, Pb-209, decays at a rate proportional to the amount present at time t and has a half-life of 3.

3 hours. If 1 gram of this isotope is present initially, how long will it take for 75% of the lead to decay? (Round your answer to two decimal places.)
Chemistry
1 answer:
astraxan [27]3 years ago
5 0

Answer:

It will take 6.6 hours for 75% of the lead to decay.

Explanation:

The radioactive decay follows first order rate law

The half life and rate constant are related as

k=rate constant=\frac{0.693}{halflife}=\frac{0.693}{3.3}=0.21h^{-1}

The rate law for first order reaction is

time=\frac{1}{k}(ln[\frac{A_{0}}{A_{t}}]

Where

A0 = initial concentration = 1 g

At= final concentration = 0.25 g (as 75% undergoes decay so 25% left]

time=\frac{1}{0.21}(ln(\frac{1}{0.25})=6.6hours

You might be interested in
Calculate the Molar Mass in g/mol of Ammonium Sulfate, (NH4)2(SO4)
saw5 [17]

Answer:

132g/mol

Explanation:

The problem here is to find the molar mass of the compound in g/mol

To solve this problem, we simply sum the atomic masses of the atoms in the compound:

   (NH₄)₂ SO₄:

  Atomic mass of N  = 14g

   Atomic mass of H  = 1g

  Atomic mass of S  = 32g

  Atomic mass of O = 16g

So;

   Molar mass = 2[(14 + 4(1))] + 32 + 4(16)  = 132g/mol

6 0
3 years ago
Draw a structural formula of an alkene or alkenes (if more than one) that undergo acid-catalyzed hydration and without re-arrang
sergij07 [2.7K]

Answer:

See explanation

Explanation:

Hydration of alkenes is a common reaction in organic chemistry. Hydration is simply the addition of water to an alkene. This is an acid catalysed reaction as we can see from the mechanism attached.

Recall that our task is to carry out the synthesis of 2-butanol using an alkene starting material in which there will be no rearrangement of the intermediate carbocation. If we start with the compound shown in the image (but-2-ene), the first step is the formation of the secondary carbocation. This is followed by the addition of water. Subsequently, the added water is deprotonated by another water molecule to yield 2-butanol and the acid catalyst. All these steps have been clearly outlined in the image attached.

5 0
4 years ago
What is light tell definition ​
swat32

Answer:

1..the natural agent that stimulates sight and makes things visible.

2.an expression in someone's eyes indicating a particular emotion or mood.

"a shrewd light entered his eyes"

8 0
3 years ago
Read 2 more answers
How is an element different than a compound? Give an example of each
Firdavs [7]

Answer:

A compound contains atoms of different elements chemically combined together in a fixed ratio. An element is a pure chemical substance made of same type of atom.

7 0
3 years ago
Read 2 more answers
Give the structure of the expected organic product in the reaction of 3-phenylpropanal with each of the following:
Misha Larkins [42]

Answer:

Please see attachment

Explanation:

Please see attachment

6 0
4 years ago
Other questions:
  • Consider the chemical equilibrium of a soap that is present in its aqueous solution. C17H35COONa(aq) mc017-1.jpg C17H35COO–(aq)
    13·2 answers
  • Which of the following is a single replacement reaction ?
    9·1 answer
  • Calculate the ratio of the mass ratio of SS to OO in SOSO to the mass ratio of SS to OO in SO2SO2. Consider a sample of SOSO in
    11·1 answer
  • 22. Which one of the following processes has a negative value for AH°?
    10·1 answer
  • The formula for one molecule of sucrose is shown below.
    7·1 answer
  • The Drake Equation...
    12·1 answer
  • PLEASE ANSWER QUICKLY!! LOTS OF POINTS!❤
    7·1 answer
  • Chemicals that are strong acids or bases are in what categories?​
    7·1 answer
  • Why cant we carry out the combustion of magnesium in a calorimeter?
    14·1 answer
  • Although almost 80% of the atmosphere is made up of nitrogen gas, most living things
    14·1 answer
Add answer
Login
Not registered? Fast signup
Signup
Login Signup
Ask question!