It is $$6.02 \times 10$$^{23}$$ molecules of a substance.

Question 1

Which of the following best describes the difference between matter and energy?

Accepted Answer

Matter is anything that has mass and occupies space, while energy is the capacity to do work or put matter into motion.

Question 2

Which of the following is NOT one of the four elements that make up 96% of the human body?

Accepted Answer

Calcium

Question 3

A sodium atom loses one electron to become a sodium ion. What is the charge and name of this ion?

Accepted Answer

It becomes a cation with a positive charge.

Question 4

Which of the following best describes a solution?

Accepted Answer

A homogeneous mixture in which the solute is dissolved in the solvent.

Question 5

If you have 1 liter of a 1 M solution of glucose ($$C_6H_{12}O_6$), how many grams of glucose are present? (Molecular weight of glucose = 180 g/mol)

Accepted Answer

$$180$$ grams

Question 6

Which statement about isotopes is correct?

Accepted Answer

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

Question 7

Which type of chemical bond involves the sharing of electron pairs between atoms?

Accepted Answer

Covalent bond

Question 8

Which of the following is a correct statement about Avogadro's number?

Accepted Answer

It is $$6.02 	imes 10$$^{23}$$ molecules of a substance.

Question 9

Which of the following best describes an exergonic chemical reaction?

Accepted Answer

A reaction that releases energy, with products having less potential energy than reactants.

Question 10

Which of the following is true about the octet rule in chemical bonding?

Accepted Answer

Atoms tend to gain, lose, or share electrons to achieve eight electrons in their valence shell.

Question 11

A mixture of water and sand is best classified as which type of mixture?

Accepted Answer

Suspension

Question 12

Which of the following is a property of hydrogen bonds?

Accepted Answer

They are weak attractions between a hydrogen atom and an electronegative atom of another molecule.

Question 13

Which of the following is an example of a synthesis (combination) reaction?

Accepted Answer

$$A + B \rightarrow AB$$

Question 14

Which statement about chemical energy is correct?

Accepted Answer

It is stored in the bonds of chemical substances and can be released during chemical reactions.

Question 15

Which of the following best describes a colloid?

Accepted Answer

A heterogeneous mixture with large solute particles that do not settle out.

Question 16

Which of the following is true about the atomic number of an element?

Accepted Answer

It is equal to the number of protons in the nucleus.

Question 17

Which of the following is a correct statement about valence electrons?

Accepted Answer

Valence electrons are found in the outermost shell and are involved in chemical reactions.

Question 18

Which of the following is a decomposition reaction?

Accepted Answer

$$AB \rightarrow A + B$$

Question 19

Which of the following is true about energy conversions in the human body?

Accepted Answer

Some energy is always lost as unusable heat during conversions.

Question 20

Which of the following best describes a molecule?

Accepted Answer

A molecule is a general term for two or more atoms chemically bonded together.

Basic Chemistry for Anatomy & Physiology

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