19.7 Complete the Following Nuclear Equations and Identify X in Each Case

19.7 Complete the following nuclear equations and identify X in each case:

19.8 Complete the following nuclear equations and identify X in each case:

19.16 For each pair of isotopes listed, predict which one is less stable:

(a) or ,

(b) or ,

(c) or .

19.18 In each pair of isotopes shown, indicate which one you would expect to be radioactive:

(a) and ,

(b) and ,

(c) and ,

(d) and ,

(e) and .

19.19 Given that

calculate the change in mass (in kg) per mole of H2 formed.

19.20 Estimates show that the total energy output of the sun is 5 × 1026 J/s. What is the corresponding mass loss in kg/s of the sun?

19.26 A radioactive substance undergoes decay as follows:

day / mass (g) / ln mass
0 / 500 / 6.214608
1 / 389 / 5.963579
2 / 303 / 5.713733
3 / 236 / 5.463832
4 / 184 / 5.214936
5 / 143 / 4.962845
6 / 112 / 4.718499

Calculate the first-order decay constant and the half-life of the reaction.

19.27 The radioactive decay of Tl-206 to Pb-206 has a half-life of 4.20 min. Starting with 5.00 × 1022 atoms of Tl-206, calculate the number of such atoms left after 42.0 min.

19.30 In the thorium decay series, thorium-232 loses a total of 6 α particles and 4 β particles in a 10-stage process. What is the final isotope produced?