Question 1

Which of the following best describes the difference between an anion and a cation?

Accepted Answer

An anion has a negative charge due to gaining electrons, while a cation has a positive charge due to losing electrons.

Question 2

Given an element with atomic number $$Z = 8$$ and atomic mass $$A = 16$$, how many neutrons does it have?

Accepted Answer

$$A - Z = 16 - 8 = 8$$

Question 3

Which statement about isotopes is correct?

Accepted Answer

Isotopes have the same number of protons but different numbers of neutrons.

Question 4

Which of the following is an example of a compound?

Accepted Answer

H$$_2O$$

Question 5

Which type of bond involves the sharing of electrons to fill the outermost shell?

Accepted Answer

Covalent bond

Question 6

A solution has a pH of 5. Which statement is true?

Accepted Answer

It is an acidic solution.

Question 7

Which of the following best describes a dehydration synthesis reaction?

Accepted Answer

A reaction that forms molecules by removing water.

Question 8

Which statement about activation energy is correct?

Accepted Answer

Activation energy is the energy required to start a chemical reaction.

Question 9

Which of the following is true about enzymes?

Accepted Answer

Enzymes lower the activation energy required for a reaction.

Question 10

Which of the following is a correct comparison between organic and inorganic compounds?

Accepted Answer

Organic compounds are primarily carbon and hydrogen-based, while inorganic compounds may contain salts and lack both carbon and hydrogen.

Question 11

Which of the following best describes a hydrophobic molecule?

Accepted Answer

It repels water and does not dissolve easily.

Question 12

Which of the following is true about hydrogen bonds?

Accepted Answer

Hydrogen bonds are weaker than covalent and ionic bonds but are crucial for the structure of biomolecules.

Question 13

Which of the following is an example of an endergonic reaction?

Accepted Answer

Photosynthesis

Question 14

Which of the following is NOT a major group of biomolecules?

Accepted Answer

Salts

Question 15

Which bond links monosaccharides together in carbohydrates?

Accepted Answer

Glycosidic bond

Question 16

Which statement best describes the primary structure of a protein?

Accepted Answer

The sequence of amino acids linked by peptide bonds.

Question 17

Which of the following is a function of nucleic acids in cells?

Accepted Answer

Storing and transmitting genetic information

Question 18

How does saturation affect the characteristics of lipids?

Accepted Answer

Saturated lipids have no double bonds and are solid at room temperature; unsaturated lipids have double bonds and are liquid at room temperature.

Question 19

Which of the following best describes a quaternary protein structure?

Accepted Answer

The association of two or more polypeptide chains.

Question 20

Which of the following is true about ribonucleotides compared to deoxyribonucleotides?

Accepted Answer

Ribonucleotides contain ribose sugar, while deoxyribonucleotides contain deoxyribose sugar.

Atoms, Macromolecules, and Biologically Important Molecules: Study Notes

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