Question

If 14 g of a radioactive substance are present initially and 4 yr later only 7...

If 14 g of a radioactive substance are present initially and 4 yr later only 7 g​ remain, how much of the substance will be present after 7 ​yr?

Homework Answers

Answer #1

please upvote.. Thanku ?

Know the answer?
Your Answer:

Post as a guest

Your Name:

What's your source?

Earn Coins

Coins can be redeemed for fabulous gifts.

Not the answer you're looking for?
Ask your own homework help question
Similar Questions
Initially 100 milligrams of a radioactive substance was present. After 5 hours the mass had decreased...
Initially 100 milligrams of a radioactive substance was present. After 5 hours the mass had decreased by 7%. If the rate of decay is proportional to the amount of substance present at time t, determine the half-life of the radioactive substance
Initially 100 milligrams of a radioactive substance was present. After 8 hours the mass had decreased...
Initially 100 milligrams of a radioactive substance was present. After 8 hours the mass had decreased by 4%. If the rate of decay is proportional to the amount of the substance present at time t, determine the half-life of the radioactive substance. (Round your answer to one decimal place.)
If the activity of a radioactive substance is initially 591 disintegrations/min and two days later it...
If the activity of a radioactive substance is initially 591 disintegrations/min and two days later it is 299 disintegrations/min, what is the activity four days later still, or six days after the start? Give your answer in disintegrations/min.
1. Suppose that you are given a 200 gram sample of a radioactive substance with a...
1. Suppose that you are given a 200 gram sample of a radioactive substance with a half-life of 45 days. How many grams will be left after 360 days? 2. A radioactive substance is found to register 5000 counts per second on a Geiger counter. Twenty-four hours later it registers 1250 counts per second. What is its half-life? 3. If a sample emits 2000 counts per second when the detector is 1 meter from the sample, how many counts per...
An unknown radioactive substance has a half-life of 3.20 hours . If 38.3 g of the...
An unknown radioactive substance has a half-life of 3.20 hours . If 38.3 g of the substance is currently present, what mass A0 was present 8.00 hours ago?
Two radioactive waste products from nuclear reactors are strontium 38Sr90 (t1/2 = 29.1 yr) and cesium...
Two radioactive waste products from nuclear reactors are strontium 38Sr90 (t1/2 = 29.1 yr) and cesium 55Cs134 (t1/2 = 2.06 yr). These two species are present initially in a ratio N0, Sr /N0, Cs = 7.80 × 10-3. What is the ratio NSr /NCs 23 years later?
Part A You are using a Geiger counter to measure the activity of a radioactive substance...
Part A You are using a Geiger counter to measure the activity of a radioactive substance over the course of several minutes. If the reading of 400. counts has diminished to 100. counts after 78.4 minutes , what is the half-life of this substance? Express your answer with the appropriate units. Part B An unknown radioactive substance has a half-life of 3.20 hours . If 26.8 g of the substance is currently present, what mass A0 was present 8.00 hours...
You are using a Geiger counter to measure the activity of a radioactive substance over the...
You are using a Geiger counter to measure the activity of a radioactive substance over the course of several minutes. If the reading of 400. counts has diminished to 100. counts after 54.3 minutes , what is the half-life of this substance? Express your answer with the appropriate units. t1/2 = 27.2 min Correct Part B An unknown radioactive substance has a half-life of 3.20 hours . If 20.6 g of the substance is currently present, what mass A0 was...
A 53.25 g sample of a substance is initially at 28.3 °C. After absorbing 2927 J...
A 53.25 g sample of a substance is initially at 28.3 °C. After absorbing 2927 J of heat, the temperature of the substance is 115.8 °C. What is the specific heat (c) of the substance?
Phosphorus-32 (P-32) has a half-life of 14.2 days. If 450 g of this substance are present...
Phosphorus-32 (P-32) has a half-life of 14.2 days. If 450 g of this substance are present initially, find the amount Q(t) present after t days. (Round your growth constant to four decimal places.) Q(t) = What amount will be left after 17.6 days? (Round your answer to three decimal places.)