Q: Which of the following is the correct formula for calculating the density of a substance?

$$\text{Density} = \dfrac{\text{Mass}}{\text{Volume}}$$

Q: Which of the following is the correct formula for calculating specific gravity?

$$\text{Specific Gravity} = \dfrac{\text{Density of substance}}{\text{Density of water}}$$

Q: Which of the following is the correct formula for calculating molarity?

$$\text{Molarity} = \dfrac{\text{moles of solute}}{\text{liters of solution}}$$

Question 1

Which of the following statements about laboratory safety is CORRECT?

Accepted Answer

You must wear safety goggles at all times in the laboratory, regardless of the activity.

Question 2

A student is preparing a solution by dissolving 10.0 g of NaCl in enough water to make 250 mL of solution. What is the molarity of the solution? (Molar mass of NaCl = 58.44 g/mol)

Accepted Answer

$$0.68\ 	ext{M}$$

Question 3

Which of the following is the correct formula for calculating the density of a substance?

Accepted Answer

$$	ext{Density} = \dfrac{	ext{Mass}}{	ext{Volume}}$$

Question 4

A student measures the mass of a graduated cylinder as 50.00 g. After adding 25.0 mL of water, the total mass is 75.00 g. What is the density of the water?

Accepted Answer

$$1.00\ 	ext{g/mL}$$

Question 5

Which of the following is NOT a recommended practice for maintaining academic integrity in the laboratory?

Accepted Answer

Copying another student's lab report and changing the data.

Question 6

A solution is prepared by dissolving 5.00 g of glucose ($$C_6H_{12}O_6$) in 100.0 g of water. What is the mass percent of glucose in the solution?

Accepted Answer

$$4.76\%$$

Question 7

Which of the following best describes the role of thin layer chromatography (TLC) in the analysis of analgesics?

Accepted Answer

TLC separates the components of analgesic mixtures based on their polarity.

Question 8

During the synthesis of aspirin, which reactants are typically used?

Accepted Answer

Salicylic acid and acetic anhydride

Question 9

A student titrates 25.0 mL of $$0.100\ 	ext{M}$$ HCl with $$0.100\ 	ext{M}$$ NaOH. What volume of NaOH is required to reach the equivalence point?

Accepted Answer

$$25.0\ 	ext{mL}$$

Question 10

Which of the following functional groups is present in all esters?

Accepted Answer

$$-COO-$$

Question 11

A carbohydrate is classified as a monosaccharide if it:

Accepted Answer

Contains only one sugar unit

Question 12

Which of the following statements about solubility is TRUE?

Accepted Answer

Solubility of a solid in a liquid generally increases with increasing temperature.

Question 13

Which of the following is the correct formula for calculating specific gravity?

Accepted Answer

$$	ext{Specific Gravity} = \dfrac{	ext{Density of substance}}{	ext{Density of water}}$$

Question 14

Which of the following is a structural feature common to all amino acids?

Accepted Answer

A carboxyl group ($$-COOH) $$and an amino group ($$-NH_2$) attached to the same carbon

Question 15

A student is asked to calculate the percent yield of aspirin. If the theoretical yield is 5.00 g and the actual yield is 4.20 g, what is the percent yield?

Accepted Answer

$$84.0\%$$

Question 16

Which of the following laboratory practices helps prevent chemical accidents?

Accepted Answer

Cleaning up spilled chemicals immediately.

Question 17

Which of the following is the correct formula for calculating molarity?

Accepted Answer

$$	ext{Molarity} = \dfrac{	ext{moles of solute}}{	ext{liters of solution}}$$

Question 18

Which of the following is a common use of volumetric glassware in the laboratory?

Accepted Answer

Accurately measuring the volume of liquids

Question 19

Which of the following is a correct statement about the peptide bond?

Accepted Answer

It is formed between the carboxyl group of one amino acid and the amino group of another.

Question 20

A student is asked to neutralize 50.0 mL of $$0.200\ 	ext{M}$$ HCl with NaOH. How many moles of NaOH are required?

Accepted Answer

$$0.0100\ 	ext{mol}$$

CHEM 109L Laboratory Safety, Measurement, and Academic Integrity Study Guide

Guida di studio - Domande di pratica

Study guide - Flashcard