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
Answer:
The answer is
<h2>19.31 g/cm³</h2>
Explanation:
The density of a substance can be found by using the formula
From the question
mass of gold = 475.09g
volume = 24.6 cm³
The density of the gold is
We have the final answer as
<h3>19.31 g/cm³</h3>
Hope this helps you
Students performed a procedure similar to Part II of this
experiment (Analyzing Juices for Vitamin C Content) as described in the
procedure section. Given that molarity of DCP is 9.98x10-4 M, it took 16.34 ml
of DCP to titrate 10 mL of sample.
Amount of ascorbic acid = 0.050 L sample (0.01634 L DCP/0.01
L sample)( 9.98x10-4 mol DCP/L DCP)(1 mol Ascorbic acid/ 1mol DCP)(176.124
g/mol)(1000mg/1g)= 14.36 mg ascorbic acid
Based on the electronic configuration the elements are classified as metals, non metals and metalloids.
<u>Explanation:</u>
Periodic table consists of three major parts.
The left side consists of metals and the right side consists of non-metals and here Hydrogen element is the exception and in between those two regions we have metalloids, which has the dual character of both metals and non metals.
These elements can be grouped by means of its chemical properties and also due to its outermost electronic configuration.
If the valence shell electrons are same they are categorized under same group.
Hey there
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The correct answer is:
Water, carbon, and nitrogen move through living and nonliving things on Earth through processes known as C. cycles .
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Hope this helps you
