A sample contains 6.25 percent parent isotope and 93.75 percent daughter isotopes. If the half-life of the parent isotope is 58 years, how old is the sample?
Answers
Answer is: the sample is 232 years old.
Take 100 atoms:
After first half-life: 50% · 100 ÷ 100% = 50.
After second half-life: 0.5 · 50 = 25.
After third half-life: 0.5 · 25 = 12.5.
After fourth half-life: 0.5 · 12.5 = 6.25.
6.25 ÷ 100 · 100% = 6.25%.
4 half-lives will it take before only about 6.25% of the original sample remains.
t = 4 · 58 y.
t = 232 y.
Related Questions
1. Science is different than many other ways of thinking because it is based on-opinions-facts-personal viewpoints-none of the above
Write the ionic equation for the reaction of aqueous propanoic acid with aqueouspotassium hydroxide.
Explain what you think what happen to rubber if too manyn cross limks are formed.
The troposphere is warmed by the _____.energy of the entire solar system incoming radiation of the sun radiated heat from the Earth's surface atmospheric air circulation help plz
formation of clouds
metal corroding in salt water
sugar dissolving in water
separating salt from seawater
Answers
Answer: C. metal corroding in salt water
Explanation:
A. glass
B. pottery
C. ice
D. gold
Answers
Final answer:
Gold is malleable while glass, pottery, and ice are not.
Explanation:
Malleability is the ability of a material to be hammered or rolled into thin sheets without breaking. Gold is highly malleable and can be shaped into various forms, such as jewelry and gold leaf. Glass, pottery, and ice, on the other hand, are not malleable because they will break or shatter when hammered or rolled into thin sheets.
Gold is malleable because its metallic bonds allow its atoms to slide past one another without breaking. Glass, pottery, and ice lack these bonds and have a more rigid structure, making them non-malleable. Instead, glass and pottery are brittle, while ice can fracture under stress due to its molecular structure.
Learn more about Malleability of Materials here:
#SPJ6
Answers
Answer: Boiling point
Explanation:
Boiling point is the temperature where the vapor pressure of a liquid equals the pressure of the gas present above it.
The normal boiling point of a liquid is the temperature at which its vapor pressure is equal to one atmosphere.
Boiling point depends on the intermolecular forces present between the molecules. More are the intermolecular forces, lesser will be the vapor pressure and thus more heat will be supplied to make vapor pressure equal to the atmospheric pressure. Thus higher will be the boiling point.
Normal boiling point for water is .
to separate the dissolved part of a solution into layers
to separate a mixture by heating it for a long period of time
to separate the undissolved particles of a mixture into layers
Answers
The correct answer is the last answer choice
Answers
The volume of the NaOH that we would now need for the neutralization reaction is32.5 mL.
What is neutralization?
Neutralization is a chemical reaction in which an acid reacts with a base to form a salt and water. In this reaction, the hydrogen ions from the acid combine with the hydroxide ions from the base to form water
Number of moles of HCl = 40/1000 L * 0.65
= 0.026 moles
Since the reaction is 1:1, there would be 0.026 moles
of the NaOH used as such we would now have that;
Volume of the NaOH = 0.026 moles/0.8 M
= 32.5 mL
Learn more about neutralization:brainly.com/question/27891712
#SPJ4
Answers
In gamma decay, no change in proton number occurs, so the atom does not become a different element