Which radioactive sample would contain the greatest remaining mass of the radioactive isotope after 10 years?
A. 2.0 grams of 198 Au
B. 2.0 grams of 42 K
C. 4.0 grams of 32 P
D. 4.0 grams of 60 Co
By the way the numbers next to the elements are their atomic masses. thanks again
You must look up the halflife of each of the isotopes. Surely you have a text or notes that will furnish this. Co60 is the only one I know from memory for I worked with it many years ago. It is 5.1 years halflife. Then half of the mass will remain after 1 half life, 1/4 will remain after two half lives, etc.
You can also use
ln(No/N)=kt I can help with that if you need help after you obtain the half lives.
 👍
 👎
 👁
 ℹ️
 🚩
2 answers

It is D
4.0 grams of 60Co 👍
 👎
 ℹ️
 🚩
answered by Anonymous 
It is choice (D)
4.0 grams of 60Co 👍
 👎
 ℹ️
 🚩
answered by Anonymous
Answer this Question
Related Questions

AP science
You have 180 g of a radioactive substance. It has a halflife of 265 years. After 1,325 years, what mass remains?
 asked by Anonymous
 4,172 views

Math
A 15g sample of radioactive iodine decays in such a way that the mass remaining after t days is given by m(t) = 15e^(−0.051t), where m(t) is measured in grams. After how many days is there only 3 g remaining?
 asked by Zach
 1,364 views

math
3. Write the exponential growth function to model the following situation: A population of 422, 000 increases by 12% each year. 4. At t = 0 there are 50 grams of a radioactive isotope. The isotope has a halflife of 16 minutes. Use the exponential decay
 asked by nancy
 2,514 views

chemistry
Gallium is a metal with a wide variety of uses. Some of its applications include computer memory chips, light emitting diodes and lasers. Radioactive isotopes of gallium are used to image the human body and locate tumors. Naturally occurring gallium
 asked by billy
 10,926 views

Physics
A radioactive sample initially contains N atoms. After three half lives the number of atoms that disintegrated is ?
 asked by Majiri
 614 views

chemistry
What is the nuclear symbol for the radioactive isotope of copper with a mass number of 60?
 asked by chache
 4,940 views

Algebra ASAP
The halflife of krypton91 ^(91Kr) is 10 seconds. At time t = 0 a heavy canister contains 6 g of this radioactive gas. (a) Find a function m(t) = m02^−t/h that models the amount of ^(91)Kr remaining in the canister after t seconds. m(t) = (b) Find a
 asked by Fay
 8,005 views

Physics
Consider a radioactive sample with a halflife of one week. How much of the original sample will be left at the end of the second week? The third week? The fourth week?
 asked by Tracee
 5,346 views

Chem 2
The halflife for the radioactive decay of U238 is 4.5 billion years and is independent of initial concentration. a) How long will it take for 10% of the U238 atoms in a sample of U 238 to decay? b)If a sample of U238 initially contained 1.9×1018
 asked by Kristina
 4,552 views

Precalc
Element X is a radioactive isotope such that every 86 years, its mass decreases by half. Given that the initial mass of a sample of Element X is 730 grams, how much of the element would remain after 9 years, to the nearest whole number?
 asked by Josh
 2,534 views

science
The halflife of carbon 14 is 5730 years. if a 1 g sample of old carbon is 1/8 as radioactive as 1 g of a current sample, then the age of the old sample is about ___________years. 22,900 17,200 11,500 716
 asked by chuck
 2,438 views

10th Grade Chemistry
Hi! I am taking the Unit 8 Lesson 10 chem test now and I have a C in this class so I need to get all the answers correct... If you don't know all that's ok but if you know some please help, thank you! (Connections Academy) 1. In a nuclear reaction, which
 asked by Yarielis
 1,358 views

Science
Which allowed scientists to determine that Earth was at least 4.3 billion years old?(1 point) Responses chemical reactivity of zircon ions chemical reactivity of zircon ions the radioactive decay of uranium to lead the radioactive decay of uranium to lead
 asked by Ayden wells
 106 views

Chemistry
Gallium65, a radioactive isotope of gallium, decays by first orderkinetics. The halflife of this isotope is 15.2 min. How long would it take for 7/8 of a sample of this isotope to decay? 15.2 min 30.4 min 45.6 min 48.0 min I'm not sure how to do this. I
 asked by Val
 3,453 views

Radioactivity
Iodine131 is a radioactive isotope. After 8.00 days, 50.2% of the sample remains. What is the half life of 131I?
 asked by Jessica
 2,947 views

math
8. The halflife of a certain radioactive material is 71 hours. An initial amount of the material has a mass of 722 kg. Write an exponential function that models the decay of this material. Find how much radioactive material remains after 17 hours. Round
 asked by emily
 3,312 views

Chemistry
Iodine 131 is a radioactive isotope. After 4.00 days, 70.8% of a sample of 131I remains.What is the half life of 131I?
 asked by Natalie
 4,352 views

Calculus
A fragment of bone is discovered to contain 20% of the usual carbon14 concentration. Estimate the age of the bone to the nearest hundred years, given that Carbon1 is radioactive with halflife of 5730 years and the rate of decay is given by the following
 asked by Kristin
 1,212 views

algebra
In a lab experiment, the decay of a radioactive isotope is being observed. At the beginning of the first day of the experiment the mass of the substance was 1300 grams and mass was decreasing by 14% per day. Determine the mass of the radioactive sample at
 asked by Anonymous
 1,247 views

Calculus
A certain radioactive material is known to decay at a rate proportional to the amount present. A block of this material originally having a mass of 100 grams is observed after 20 years to have a mass of only 80 grams. Find the halflife of this radioactive
 asked by Frida
 1,071 views
Still need help?
You can ask a new question or browse existing questions.