Answer:
3.125 grams
Explanation:
Applying,
R = (
)R'............... Equation 1
Where R = Original mass of Astatine-211, R' = mass of Astatine-211 left after decay, t = total disintegeration time, n = halflife of Astatine-211
make R' the subject of the equation
R' = R/()............ Equation 2
From the question,
Given: R = 50 grams, t = 28 hours, n = 7 hours
Substitute into equation 2
R' = 50/(
)
R' = 50/(2⁴)
R' = 50/16
R' = 3.125 grams
Answer:
it's the same if rounded off to the nearest decimal or slightly different if not.
Explanation:
The enthalpy of formation is -431.6 kJ, while the bond energy of H-Cl is -432 kJ.
Answer:
As the description in the question shows, Kaley is taking careful and regular measurements. Hence, her experimental method is correct.
Kaley has also developed a hypothesis and the experiment she conducted is also valid hence there is no problem in these steps.
There is no mistake being done by her in depicting the results of the experiment.
Hence, the only thing which we can say is missing from the experiment is the past researches which scientists might have made on this topic.
Explanation:
Isotopes are elements with the same number of protons but different number of neutrons
Water!!! (H2O) ........... :)
