SCIN 131 Lesson 5 Quiz

Your grades have been posted and your short answer questions graded with comments. Thanks! Prof Heath
Part 1 of 3 - 24.0/ 52.0 Points
Question 1 of 25
4.0/ 4.0 Points
A compound responsible for the odor of garlic has a molecular weight of 146 g/mol. A 0.650 g sample of the compound contains 0.321 g of carbon, 0.044 g of hydrogen, and 0.285 g of sulfur. What is the molecular formula of the compound?
 A. C3H5S
 B. C3H15S3
 C. CH5S
 D. C6H10S2 Feedback:Great! Empirical Formula discussed in Chapter 6.2.
Question 2 of 25
4.0/ 4.0 Points
`I was planting a tree in my backyard and hit something hard. I dug it out and decided it was an ore of copper. I took its mass, and it was 65.0 grams. After some tricky experiments in my basement lab, I managed to extract 11.5 grams of copper. What is the mass percent of copper in the ore I discovered?
 A. 63.5%
 B. 18.1%
 C. 5.65%
 D. 17.7%
Feedback:Great! Mass percent discussed in Chapter 6.2.
Question 3 of 25
0.0/ 4.0 Points
`Benzoic acid (C7H6O2) is a common over-the-counter medication for mild acne. What is the mass
percent of carbon in this medicine?
 A. 4.95%
 B. 68.8
 C. 26.2%
 D. 46.7%
Feedback:Mass percent discussed in Chapter 6.2.
Question 4 of 25
0.0/ 4.0 Points
`I have some aliens in my basement who have developed a chemical weapon in an attempt to escape. I was able to survive the first attack and capture a sample of the dangerous gas. I analyzed it to find that it had a molar mass of 648.52 grams, and its empirical formula is C5H11N2O2P. What is its molecular formula?
 A. C20H44N8O8P4
 B.