1. Fluorine-21 has a half-life of approximately 5 seconds. How much of a 200 gram sample would remain after 1 minute.

Utherford proposed that atoms have positive nuclei which statement correctly describes the nucleus of an atom?

According to Table I, which equation represents a change resulting in the greatest quantity of energy absorbed?

How many moles are there in 500cm3 of a 0.5mol/dm3 solution of sulfuric acid?

In lab, you actually produced, 56.7 grams of potassium chloride but the equation shows you should have made 58.9 grams. What is your percent yield to the tenths place?

What type of element is helium in the periodic table?

How do the relative concentrations of hydronium ions and hydroxide ions compare in acidic solution?

Give the name of the orange metal visable after one week

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) ?