Answer:
a) a0 was 46.2 grams
b) It will take 259 years
c) The fossil is 1845 years old
Explanation:
<em>An unknown radioactive substance has a half-life of 3.20hours . If 46.2g of the substance is currently present, what mass A0 was present 8.00 hours ago?</em>
A = A0 * (1/2)^(t/h)
⇒ with A = the final amount = 46.2 grams
⇒ A0 = the original amount
⇒ t = time = 8 hours
⇒ h = half-life time = 3.2 hours
46.2 = Ao*(1/2)^(8/3.2)
Ao = 261.35 grams
<em>Americium-241 is used in some smoke detectors. It is an alpha emitter with a half-life of 432 years. How long will it take in years for 34.0% of an Am-241 sample to decay?</em>
t = (ln(0.66))-0.693) * 432 = 259 years
It will take 259 years
<em>A fossil was analyzed and determined to have a carbon-14 level that is 80% that of living organisms. The half-life of C-14 is 5730 years. How old is the fossil?</em>
<em />
t = (ln(0.80))-0.693) * 5730 = 1845
The fossil is 1845 years old
The correct answer really is B.
If you are directed to break that rule then you better be in a high level chemistry class. When I taught things like that I insisted that students just wait until the chemical permeated the fume cabinet and even then I was always very nervous.
Sometimes you have to know when to ignore a bad direction. If you are working with chlorine, for example, you should be especially careful. That stuff was used in WWI as part of a chemical warfare technique. Many men suffered grotesque deaths by breathing it in, particularly if they were in trenches. Chlorine is heavier than air. It sinks to the lowest level.
alternative acids are more cost-effective and allow for flavor expression through nontraditional methods and ingredients, making for increased versatility.
It is false because an endothermic reaction will also start when energy is received from the environment when there is no solution involved
The term that describes the data that deals with the traits of an object is the term qualitative.
<h3>What is qualitative data?</h3>
The term qualitative data refers to data that is collected from findings that are carried out. It gives the idea of the individual parts of the data that is collected and how it can be accurately used.
It may be pertinent to add that the term "qualitative" come from the word "quality" which has to do with the way in which a thing is or is thought to be. This term is often of very much important when we are dealing with the classification and presentation of data.
Thus the term that describes the data that deals with the traits of an object is the term qualitative.
Learn more about qualitative:brainly.com/question/14265131
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