Amount of Niobium-91 initially
= 300/91 =3.2967mol
2040 years = 3 ×680 = 3 half-lives
therefore, amount left = 0.4121mol
mass of Niobium-91 remaining = 0.4121 ×91 =37.5g
Answer:
im sorry, but im not sure
Explanation:
Answer:
Atomic number, the number of a chemical element in the periodic system, whereby the elements are arranged in order of increasing number of protons in the nucleus. Accordingly, the number of protons, which is always equal to the number of electrons in the neutral atom, is also the atomic number.
Explanation:
Answer:
0.484 mole
Explanation:
1 mole of glucose reacts with 6 moles of O2, producing :
6 moles of CO2
6 moles of H2O
678 kcal
Using rule of three you have:
1 mole of glucose -> 678 kcal
x mole of glucose -> 328 kcal
x = 328/678 * 1 =0.484 mole
