Blog

If matter is uniform throughout and cannot be separated into other substances by physical processes, but can be decomposed into other substances by chemical processes, it is called a(n) __________.

The goal of the United Nations is to keep world peace and security.

In charge of an expedition sponsored by King Ferdinand and Queen Isabella of Spain, he sailed west in 1492 and landed with Taino inhabitants at San Salvador whom he called “Indians” mistakenly believing he was in Asia.

Balance the following reaction and determine the moles of aluminum needed to react with 2.5 moles of iodine. Al + I2 → AlI3 Write out your calculations and answers clearly, with all numbers labeled correctly, on a piece of paper.  Right after submitting your exam, upload your photos to the Assignment Box, “Calculations for Exam 2 (Chapter 3)”

Assignments can be reopened, if I miss the due date because I was at work.

Nitrogen combines with lithium as shown below.  If we want to produce 3.60 mol of lithium nitride, how many moles of lithium would we need to start with? (Nitrogen is in excess.)             6Li(s) + N2(g)  →  2Li3N(s)

If a solution is prepared by diluting 40.0 mL of 0.200 M CsCl to 250.0 mL, what is the new solution’s concentration in molarity?

Each curve on the graph below represents a different gas.  Which one of the gases has the lowest molar mass?

Atoms X, Y, Z, and R have the following nuclear compositions:               Which two are isotopes?

What is the abbreviation for “three times a day”?