Atomic mass $$= \text{Number of protons} + \text{Number of neutrons}$$

Valence electrons $$= \text{Group number} ($$for main group elements)

Question 1

Which of the following best describes a control variable in a scientific experiment?

Accepted Answer

A variable that is kept constant to ensure a fair test.

Question 2

Charles Darwin’s theory of natural selection is based on which of the following key concepts?

Accepted Answer

Traits that increase survival and reproduction become more common in a population over time.

Question 3

Which of the following is the correct formula for calculating the atomic mass of an element?

Accepted Answer

Atomic mass $$= 	ext{Number of protons} + 	ext{Number of neutrons}$$

Question 4

A radioactive isotope has a half-life of 10 years. If you start with 80 grams, how much will remain after 30 years?

Accepted Answer

10 grams

Question 5

Which of the following best explains why water has a high specific heat?

Accepted Answer

Hydrogen bonds between water molecules require more energy to break.

Question 6

Which property of water allows insects like water striders to walk on its surface?

Accepted Answer

Surface tension due to hydrogen bonding

Question 7

Which of the following molecules is most likely to dissolve in water?

Accepted Answer

A polar molecule like glucose

Question 8

What is the correct formula for calculating the number of valence electrons in a neutral atom?

Accepted Answer

Valence electrons $$= 	ext{Group number} ($$for main group elements)

Question 9

Which of the following best describes a covalent bond?

Accepted Answer

A bond formed by the sharing of electron pairs between atoms.

Question 10

Which of the following is a real-world application of radioactive isotopes in medicine?

Accepted Answer

Using isotopes to diagnose and treat diseases such as cancer.

Question 11

Which of the following statements about ATP is correct?

Accepted Answer

ATP is a molecule that provides energy for cellular processes.

Question 12

Which functional group is found in amino acids and is essential for protein structure?

Accepted Answer

Carboxyl group

Question 13

Which of the following best explains why ice floats on water?

Accepted Answer

Hydrogen bonds in ice create an open lattice structure, making it less dense than liquid water.

Question 14

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

Accepted Answer

Molarity $$= \frac{	ext{Moles of solute}}{	ext{Volume of solution in liters}}$$

Question 15

Which of the following best describes chemical equilibrium?

Accepted Answer

The point at which the rates of the forward and reverse reactions are equal.

Question 16

Which of the following is a correct statement about Miller’s experiment on the origin of life?

Accepted Answer

Miller’s experiment demonstrated that amino acids could be synthesized from inorganic molecules.

Question 17

Which of the following best explains the difference between hydrophilic and hydrophobic molecules?

Accepted Answer

Hydrophilic molecules dissolve in water, while hydrophobic molecules do not.

Question 18

Which of the following is a correct statement about the role of functional groups in biological molecules?

Accepted Answer

Functional groups determine the reactivity and interactions of biological molecules.

Question 19

Which of the following is the correct formula for calculating the number of neutrons in an atom?

Accepted Answer

Number of neutrons $$= 	ext{Atomic mass} - 	ext{Atomic number}$$

Question 20

A scientist is studying the effect of temperature on enzyme activity. Which is the independent variable in this experiment?

Accepted Answer

The temperature at which the reaction occurs

General Biology: Foundations, Chemistry, Water, and Organic Molecules

Study Guide - Practice Questions