1. Copper has an average atomic mass of 63.55 and has two naturally occurring isotopes, 63Cu and 65Cu. If a sample of copper contains 69.17% of 63CU, which has a mass of 62.9296. What is the mass of 65CU? (Assume 100% of the sample contains only 63Cu and 65Cu as its only isotopes. (Express your answer in 6 significant digits. Be sure to follow sig. fig rules.)

Search (Alt+Q) Pau References Mailings Review View Help There are three naturally occurring stable isotopes of magnesium: 24MB, 25Mg, and 2°Mg, which have relative abundances on Earth of 79%, 10%, and 11% respectively. Note that the atomic number of magnesium is 12. a) Calculate the binding energy (in eV) of magnesium-24, which has an atomic mass of 23.9850 AMU. The mass of a neutron is 1.0087 amu and the mass of a proton is 1.0073 amu. Using your results from parts (i) and (ii) discuss how the nucleus is held together. b) The radioisotope of magnesium with the longest half-life is magnesium-28, with a half-life of 20.9 hrs. Magnesium-28 decays through B- decay into aluminium-28. With reference to fundamental particles, describe the process which occurs in beta minus decay. Hence determine the equation for the decay of magnesium-28 into aluminum-28.

3D. Write the equation for the alpha decay of Thorium-232. b) Write the element that is formed in the alpha decay of Thorium-232. Your answer

3C. Write the equation for the beta-positive decay of Potassium-40. b) Write the element that is formed in the beta-positive decay of Potassium- 40. Your answer

5. A sample of protactinium -234 of mass 100 g has a half-life of G-7 hours. A. what praction of the sample has not decayed after 20-1 hours? B. What is the mass of undecayed protactinium -234 after this period of time...

Boron has two naturally occurring isotopes, boron-10, andboron-11. Boron-10 has a mass of 10.0129 relative tocarbon-12 and makes up 19.78 percent of all naturallyoccurring boron. Boron-11 has a mass of 11.00931 comparedto carbon-12 and makes up the remaining 80.22 percent. What isthe atomic weight of boron?

An unknown element X has the following isotopes: ⁶⁴X (49.00% abundant), ⁶⁶X (28.00% abundant), ⁶⁸X (23.00% abundant). What is the average atomic mass in amu of X?

1. Determine the element created, and its atomic number and mass number when Lead-204 undergoes alpha decay, producing a stable isotope. Write the nuclear reaction equation for this alpha decay. lead 204 => 204 82 Pb

A picture supposedly painted by Vermeer (1632-1675) contains 99.5% of its carbon-14 (half-life of 5730 years).  1. Is this enough information to determine if the picture is a fake?  2. What is the strategy for attacking the problem?

A periodic table might list the average atomic mass of magnesium as being 24.312 u, which is the result of weighting the atomic masses of the magnesium isotopes according to their natural abundances on Earth.The three isotopes and their masses are 24Mg (23.985 04 u), 25Mg (24.985 84 u), and 26Mg (25.982 59 u).  The natural abundance of 24Mg is 78.99% by mass (that is, 78.99% of the mass of a naturally occurring sample of magnesium is due to the presence of 24Mg).What is the abundance of (a) 25Mg and (b) 26Mg?