General Chemistry Answers

Phosphorus-32 is used to treat a certain form of leukemia. Starting with 10.0mg, what mass of phosphorus-32 would remain after 57.2 days? The half-life of phosphorus-32 is 14.3 days.

An archaeologist discovers a wooden mask whose carbon-14 to carbon-12 ratio is one- sixteenth the ratio measured in a newly fallen tree. How old does the wooden mask seem to be, given this evidence and the ½-life of carbon – 14 to be 5715 years?

The half-life of iodine-131 is approximately 8 days. How much of an original 272g sample would be left after 32 days?

A decay series ends with a _____. Fissionable nuclide Positron emission Stable nuclide Transuranium element

. Consider the following system at equilibrium: SiF4(g) + 2 H2O(g)  SiO2(g) + 4 HF(g) + 103.8 kJ (a) Is the reaction endothermic or exothermic? (b) If HF is added, in which direction will the reaction shift in order to reestablish equilibrium? After the new equilibrium has been established, will the final molar concentrations of and HF increase, decrease, or remain the same? (c) If heat is added, in which direction will the equilibrium shift?

What would happen to the concentrations of each substance in the system H2(g) + I2(g)  Δ2 HI(g) upon adding (a) more H2 and (b) more HI. 2. 2 CO2(g) + N2(g) == C2N2(g) + 2 O2(g) ΔH = + 1095.9 kJ (a) if the volume of the reaction vessel is increased (b) if O2 is added (c) if the temperature is increased (d) if the concentration of N2 is increased

Applying Le Châtelier’s principle, in which direction will the equilibrium shift, (if at all)? CH4(g) + 2 O2(g) == CO2(g) + 2 H2O(g) H = + 802.3 kJ (a) if the temperature is increased (b) if a catalyst is added (c) if CH4 is added (d) if the volume of the reaction vessel is decreased