Q: Which functional group is present in ethanol and is important in biological chemistry?

Hydroxyl group ($$-\text{OH})$$

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

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

Question 1

Which of the following best describes the difference between a compound and a mixture?

Accepted Answer

A compound is made of two or more elements chemically bonded, while a mixture contains substances physically combined without chemical bonds.

Question 2

A nurse needs to prepare a saline solution by dissolving 5.0 g of NaCl in enough water to make 250 mL of solution. What is the concentration of NaCl in the solution in $$	ext{g/L}$$?

Accepted Answer

20 $$	ext{g/L}$$

Question 3

Which of the following statements about acids and bases is correct?

Accepted Answer

Acids have a pH less than 7 and bases have a pH greater than 7.

Question 4

Which equation correctly represents the relationship between pressure, volume, and temperature for an ideal gas?

Accepted Answer

$$PV = nRT$$

Question 5

A sample of gas occupies 2.0 L at 1.0 atm and 300 K. If the pressure is increased to 2.0 atm and the temperature is decreased to 150 K, what will be the new volume?

Accepted Answer

0.5 L

Question 6

Which of the following is a physical change?

Accepted Answer

Melting ice into water

Question 7

What is the molar mass of glucose ($$	ext{C}_6	ext{H}_{12}	ext{O}_6$$)?

Accepted Answer

180 $$	ext{g/mol}$$

Question 8

Which of the following best describes an ionic bond?

Accepted Answer

A bond formed by the transfer of electrons from one atom to another.

Question 9

A patient receives a radioactive isotope for imaging. Which type of nuclear emission is most likely used for medical imaging?

Accepted Answer

Gamma emission

Question 10

Which functional group is present in ethanol and is important in biological chemistry?

Accepted Answer

Hydroxyl group ($$-	ext{OH})$$

Question 11

How many moles are in 36 g of water ($$	ext{H}_2	ext{O}$$)?

Accepted Answer

2 moles

Question 12

Which of the following is the correct empirical formula for hydrogen peroxide ($$	ext{H}_2	ext{O}_2$$)?

Accepted Answer

$$	ext{HO}$$

Question 13

Which of the following is a common misconception about the periodic table?

Accepted Answer

Elements in the same period have similar chemical properties.

Question 14

Which gas law explains why a balloon shrinks when placed in a freezer?

Accepted Answer

Charles's Law ($$V \propto T at $$constant pressure)

Question 15

Which of the following is NOT a property of alkanes?

Accepted Answer

They contain at least one double bond.

Question 16

A student mixes two clear solutions and observes a precipitate forming. What type of change has occurred?

Accepted Answer

Chemical change

Question 17

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

Accepted Answer

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

Question 18

Which of the following best describes the role of stoichiometry in a chemical reaction?

Accepted Answer

It allows calculation of the amount of products formed from a given amount of reactants.

Question 19

Which of the following is a real-world application of nuclear chemistry in medicine?

Accepted Answer

Using radioactive isotopes for cancer treatment (radiotherapy)

Question 20

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

Accepted Answer

$$	ext{pH} = -\log_{10}[	ext{H}^+]$$

CHE 141: Introduction to Chemistry and Lab – Syllabus and Course Structure

Guida di studio - Domande di pratica

Study guide - Flashcard