The half-life of a radioactive isotope is 20.0 minutes. What is the total amount of a 1.00-gram sample of this sample of this isotope remaining after 1.00 hour?
Answers
Answer: 0.125 grams
Explanation:
Radioactive decay follows first order kinetics.
Half-life of give isotope = 20 minutes
N = amount left after time t= ?
= initial amount = 1.0 g
= rate constant
t= time = 1 hour = 60 min
N=0.125g
Thus amount left after 1 hour is 0.125 grams
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Answers
Answers
Final answer:
Starch is easily digested by humans due to the presence of enzymes breaking its α-glucose bonds, while humans lack the enzymes to break the β-glucose bonds in cellulose, rendering it indigestible but essential as dietary fiber.
Explanation:
Starch and cellulose are both polysaccharides produced by plants. Their structural differences, however, determine how they can be digested by animals. Starch is made up of α-glucose molecules, which are joined together by 1-4 and 1-6 glycosidic bonds, forming a helical structure. The human digestive system has enzymes like amylase that can break these bonds, enabling the digestion of starch.
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B. observed wavelength of light
C. speed of light
D. mass of the particulate matter
Answers
Answer: B. observed wavelength of light
Explanation: The relation of Planck's constant relating the Joules of energy absorbed/released by matter is usually used to determine the energy of the photon. The mathematical expression is -
E= h c /
Thus as we can observe that the energy is directly proportional to the speed of light and inversely proportional to the wavelength of the light.
Thus , we can say that Planck's constant relates the Joules of energy absorbed/released by matter to the observed wavelength of light.
Answers
Answer:
85g
Explanation:
To convert the moles of a substance to grams we need to know the molar mass of the substance. We, as first, must obtain the molar mass of (NH₄)₂S as follows:
There are 2 atoms of N, 8 of H and 1 of S:
N = 2*14g/mol = 28g/mol
H = 8*1g/mol = 8g/mol
S = 1*32g/mol = 32g/mol
Molar mass: 68g/mol
That means 1 mole of (NH₄)₂S has a mass of 68g.
1.25moles have a mass of:
1.25moles * (68g/mol) =
85g
(B) Climate zones at high latitudes are cooler because they are closer to the equator.
(C) Climate zones at high latitudes receive a lot of precipitation because they are farther from the equator.
(D) Climate zones at low latitudes receive little precipitation because they are closer to the ocean.
Answers
(A) Climate zones at low latitudes are hotterbecause they receive more direct sunlight. This is because the Earth's surface at the equator is closer to the sun and therefore receives more direct sunlight
Additionally, the distance of a region from the equator affects its precipitation pattern, with regions closer to the equator generally receiving more precipitation than regions at higher latitudes.
As a result, the tropics, which lie near the equator, tend to be warmer than other regions. In contrast, regions at high latitudes receive less direct sunlight due to the curvature of the Earth's surface, resulting in colder temperatures.
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Answers
Answer: Molecular Formulas. Molecular formulas are a compact chemical notation that describe the type and number of atoms in a single molecule of a compound. Identify the molecular formula of a compound given either its name or structural formula.
Explanation: