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Americium-241, used in smoke detectors, creates a steady electrical current due to its radioactivity. When smoke particles disrupt this current, it triggers the alarm.  How many neutrons are there in one atom of this isotope, 241Am?

The element, Indrajitium (Id), named after the CHM 113 lab instructor who discovered it while working at ASU, has three naturally occurring isotopes. The masses and % natural abundances of these isotopes are shown in the table below: What mass should be listed on the periodic table for this new element?

What is the oxidation number of the chlorine atom in the compound, KClO3?

Paying attention in lecture question! In Lecture Quiz #2, we explored the property of density by examining a clip from Indiana Jones and the Raiders of the Lost Ark.  In the clip, Indy tries to steal a gold statue by replacing it on a pedestal with another object.  What was this object?

What is the minimum amount of time a professor must spend grading for the time to fall in the top 10% of all exam grading times?

How many nitrogen atoms are there in 10 g of NH4NO3?

How many protons, neutrons, and electrons are there in one atom of 63Cu?

The shortest player in NBA history, Muggsy Bogues, stood 5 feet, 3 inches tall.  How many carbon atoms would you need to stack on top of each other in order to reach this height? (The diameter of a carbon atom is 67 pm, 1 ft = 12 in, 1 in = 0.0254 m).

A piece of pure aluminum foil is cut to dimensions of 3.00 cm x 8.00 cm and its mass is measured as 0.265 g.  Given the density of Al is 2.70 g /cm3, and the diameter of a single Al atom is 2.86 x 10-8 cm, how many Al atoms span the thickness of the foil?**

What is proper syntax to find the probability that a randomly selected exam will require more than 15 minutes to grade?