Question 1

Which of the following statements best describes an atom?

Accepted Answer

An atom is the smallest unit of matter that retains the properties of an element.

Question 2

Which subatomic particle determines the atomic number of an element?

Accepted Answer

Proton

Question 3

Given the atomic number ($$Z) $$and mass number ($$A) of an $$atom, which equation correctly calculates the number of neutrons ($$N$$)?

Accepted Answer

$$N = A - Z$$

Question 4

Carbon-12 and Carbon-14 are isotopes of carbon. Which of the following is TRUE about their atomic structure?

Accepted Answer

They have the same number of protons.

Question 5

Which of the following elements is NOT one of the four most abundant elements in living organisms?

Accepted Answer

Phosphorus

Question 6

A neutral atom of oxygen has 8 protons. How many electrons does it have?

Accepted Answer

8

Question 7

Which of the following best describes a covalent bond?

Accepted Answer

A bond formed by the sharing of electrons between atoms.

Question 8

Which type of bond is formed when electrons are shared unequally between two atoms due to a difference in electronegativity?

Accepted Answer

Polar covalent bond

Question 9

Which of the following is considered a weak non-covalent chemical bond important in biological systems?

Accepted Answer

Hydrogen bond

Question 10

If an atom gains an electron, what is the resulting charge?

Accepted Answer

Negative

Question 11

Which equation correctly represents the calculation of the average atomic mass ($$M_{avg}) of an $$element with two isotopes, $$M_1$$ and $$M_2$$, with abundances $$a_1$$ and $$a_2$$?

Accepted Answer

$$M_{avg} = a_1$ M_1$ + a_2$ M_2$

Question 12

Which of the following best explains why water is a polar molecule?

Accepted Answer

Oxygen is more electronegative than hydrogen, causing unequal sharing of electrons.

Question 13

Which of the following statements about electron shells is correct?

Accepted Answer

Electrons in the outermost shell have the highest energy.

Question 14

Which of the following is TRUE about the relationship between atomic number and the number of protons in an atom?

Accepted Answer

Atomic number is equal to the number of protons.

Question 15

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 16

Which of the following elements has the highest electronegativity?

Accepted Answer

Fluorine

Question 17

A radioactive isotope of carbon ($$^{14}C) $$decays with a half-life of 5,730 years. If a sample originally contains 100 grams of $$^{14}C$$, how much will remain after 11,460 years?

Accepted Answer

25 grams

Question 18

Which of the following is NOT a property of compounds?

Accepted Answer

Retain the properties of their constituent elements.

Question 19

Which of the following best describes a hydrogen bond?

Accepted Answer

A weak attraction between a hydrogen atom and an electronegative atom such as oxygen or nitrogen.

Question 20

Which of the following statements is TRUE regarding the electron configuration of a neutral neon atom ($$Ne) $$with atomic number 10?

Accepted Answer

It has 8 electrons in its outer shell.

The Chemical Context of Life: General Biology Study Notes

Guida di studio - Domande di pratica

Study guide - Flashcard