The half-life of Zn-71 is 2.4 minutes. if one had 100.0 grams at the beginning, how many grams would be left after 7.2 minutes has elapsed?

What is the ph of a 1 m solution of ammonium hydroxide?

Why science can answer some questions, but not others

You have on hand a 14% (w/v) topical antiseptic solution. you receive and order for 1 l of a 1:4000 solution. how much of what is on hand is needed to fill this order?

What is the volume of HCl gas required to react with excess magnesium metal to produce 6.82 L of hydrogen gas at 2.19 atm and 35.0 °C? 2 HCl (g) + Mg (s) ? MgCl2 (s) + H2 (g)

If the stock bottle is labled 15mg/mL and the other dose of 15.0mg, how many milliliters will the nurse draw up in the syringe

What is the rough er connected to

Two students design an experiment to see if pushing or pulling a box across the floor is more effective. The first student pushes the box across the floor a distance of 20 feet and the second student times how long it takes.

15.00 g of NH4HS (s) is introduced into a 500. mL flask at 25 °C, the flask is sealed, and the system is allowed to reach equilibrium. What is the partial pressure of ammonia in this flask if Kp = 0.108 at 25 °C for: NH4HS (s) ⇄ NH3 (g) + H2S (g) ?

Among elements 1-18, which element or elements have the smallest effective nuclear charge if we use the equation zeff=z-s to calculate zeff? check all that apply.

Two clear solutions are placed in separate beakers. The first solution has a pH of 4, and the pH of the second solution is unknown. If the two solutions are mixed and the resulting pH is 5, the second solution must have