30 Which radioisotopes have the same decay mode and have half-lives greater than 1 hour?

(1) Au-198 and N-16 (3) 1-131 and P-32

(2) Ca-37 and Fe-53 (4) Tc-99 and U-233

Consider the total ionic equation below. 2 upper N upper H subscript 4 superscript plus, plus 2 upper O upper H superscript minus, plus 2 upper H superscript plus, plus upper S upper O subscript 4 superscript 2 minus right arrow 2 upper N upper H

From the following enthalpy of reaction data and data in Appendix C, calculate ΔH∘f for CaC2 (s) : CaC2 (s) + 2H2O (l) →Ca (OH) 2 (s) + C2H2 (g) ΔH∘=-127.2kJ

Identify the trend in bond length of the hydrogen-halide molecule and explain why it exists.

The quinine in tonic water shines a strange blue-white colour when lit with UV light. Explain what is happening here.

Copper (l) sulfide can react with oxygen to produce copper metal by the reaction cu2s + o2 = > 2cu + so2. if 5.00 g of cu2s is used, then what is the theoretical yield of cu? a. 10.0 g b. 1.99 g c. 1.00 g d. 5.00 g e. 3.99 g

What is the standard cell potential (E°cell) for the voltaic cell based on the reaction below? Sn2 + (aq) + 2Fe3 + (aq) → 2Fe2 + (aq) + Sn4 + (aq)

G oil of wintergreen, c8h8o3 is prepared when methanol, ch3oh, is reacted with salicylic acid, c7h6o3. what is the percent yield of a reaction in which 15.3 g of oil of wintergreen is collected after 16.

How can a neutral atom become a positively-charged particle?

Mineral oil can be used in place of mercury in manometers when small pressure changes are to be measured. What is the pressure of an oxygen sample in mm of mineral oil if its pressure is 28.5 mm Hg? (d of mineral oil = 0.88 g/mL; d of Hg = 13.

To identify an unfamiliar organism, you could use a field guide and an