1. Which type of muscle tissue contracts involuntarily and is found in organs like the heart and intestines?

A. Skeletal muscle
B. Cardiac muscle
C. Smooth muscle
D. All of the above

Correct answer: C

Rationale: The correct answer is C: Smooth muscle. Smooth muscle tissue contracts involuntarily and is found in organs like the heart and intestines. Skeletal muscle is responsible for voluntary movements, and cardiac muscle is specific to the heart. Therefore, smooth muscle is the only type of muscle tissue that fits the description provided in the question, making it the correct choice. Option D, 'All of the above,' is incorrect as it includes skeletal and cardiac muscles, which do not fit the criteria of being found in organs like the heart and intestines. Understanding the differences between these types of muscle tissue is crucial for comprehending their specific functions in the body.

2. Which functional group is commonly found in ketones?

A. Hydroxyl
B. Carbonyl
C. Ester
D. Amine

Correct answer: B

Rationale: Ketones have the functional group -CO-, which is a carbonyl group. The other choices are associated with different functional groups

3. A lab needs 200ml of a 5% salt solution. They only have a 10% solution. How much 10% solution and water should be mixed?

A. 100ml 10% solution, 100ml water
B. 150ml 10% solution, 50ml water
C. 160ml 10% solution, 40ml water
D. 200ml 10% solution, 0ml water

Correct answer: B

Rationale: Rationale: 1. Let x be the volume of the 10% solution needed and y be the volume of water needed. 2. The total volume of the final solution is 200ml, so x + y = 200. 3. The concentration of the final solution is 5%, so the amount of salt in the final solution is 0.05 * 200 = 10g. 4. The amount of salt in the 10% solution is 0.1x, and the amount of salt in the water is 0, so the total amount of salt in the final solution is 0.1x. 5. Since the total amount of salt in the final solution is 10g, we have 0.1x = 10. 6. Solving for x, we get x = 100ml. 7. Substituting x =

4. The electrical conductivity of a strong acid solution is higher than that of a weak acid solution because:

A. Strong acids are more concentrated.
B. Strong acids release more hydrogen ions
C. Weak acids are better at dissolving salts.
D. Strong acids have a lower pH.

Correct answer: B

Rationale: Strong acids completely dissociate, leading to a h

5. The pH scale is used to indicate the concentration of:

A. Oxygen
B. Hydrogen ions
C. Salts
D. Sugar molecules

Correct answer: A

Rationale: The pH scale measures the concentration of hydrogen ions in a solution, indicating acidity or basicity.

6. Which of the following properties is NOT characteristic of a covalent bond?

A. Sharing of electrons between atoms
B. High melting and boiling points
C. Low electrical conductivity in solid state
D. Directional bonding

Correct answer: B

Rationale: Covalent bonds are formed by the sharing of electrons between atoms. This sharing results in the formation of molecules with directional bonding, where the atoms are held together in a specific orientation. Covalent compounds generally have low melting and boiling points compared to ionic compounds, as the intermolecular forces in covalent compounds are weaker. Additionally, covalent compounds do not conduct electricity in the solid state because the electrons are localized between the atoms and not free to move and carry charge.