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Returning from the lungs, the oxygenated blood enters this chamber…. 

Level 1 – Identifying Hazards Which of the following symbols and descriptors is incorrect.

Terminology – Acids and Bases – Level 1 Specifically for the Lewis perspective, Lewis acids are…

Charge States of Elements and Ions – Level 1 What is the oxidation number of elemental sodium?

Polyatomic Ions and Charges – Level 2 What is the typical charge found on the anion(s) and cation(s) in sodium phosphate (aq.)?

Level 2 – Ideal Gas Law Equation A student is working with a trivalent metal and 6M HCl. They want to determine the identity of the metal. First, they weighed out 5g of an unknown metal and then they added it to the reaction vessel in a similar manner to what we performed in the lab. They observed 710 mL of gas evolve. The water was approximately 25oC and the atmosphere was 1 atm. Given: R = 0.08206 (L∗atm)/(mol∗K) Determine the unknown metal’s identity.

Acids and Bases – Titration of Vinegar – Level 3 11.89 mL of 0.470 M sodium hydroxide (NaOH) was needed to titrate a 9.98 mL sample of vinegar that was being tested for FDA approval. What is the weight percent of acetic acid in the vinegar sample? Given: Vinegar Solution Density = 1.005 g/mL

Data Comprehension – Solubility Rules – Level 2 Use the table below for any solubility related questions.   Which of the following molecules would be soluble in water?

Precision and Accuracy – Level 1 A general chemistry student took the mass of a sample of Solution Q five times. The following table includes the results of those five measurements. Measurement # 1 2 3 4 5 Mass (g) 14.005 14.006 14.005 14.004 14.006 The true value of solution Q was 15.765 g. The lab holds 5% as the maximum tollerance for accuracy and/or precision. From this it would be reasonable for the student to conclude that the balance is _________________.

Glassware Accuracy – Level 2 Rank the following glassware in terms of accuracy from most to least. I: BurretII: Volumetric FlaskIII: Graduated CylinderIV: BeakerV: Disposable Pipette (ungraduated)