Question 1

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

Accepted Answer

High surface tension due to hydrogen bonding

Question 2

What is the maximum number of electrons that can be held in the second electron shell of an atom?

Accepted Answer

$$8$$

Question 3

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

Accepted Answer

Hydrogen bonds in ice create a lattice that is less dense than liquid water

Question 4

A sodium atom ($$Na) $$has an atomic number of $$11$$ and a mass number of $$23. $$How many neutrons does it have?

Accepted Answer

$$12$$

Question 5

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

Accepted Answer

Covalent bond

Question 6

What is the correct balanced chemical equation for the dissociation of water?

Accepted Answer

$$H_2O \rightarrow H^+ + OH^-$$

Question 7

Which statement best describes a polar covalent bond?

Accepted Answer

Electrons are shared unequally, resulting in partial charges

Question 8

Why does water have a high specific heat compared to other substances?

Accepted Answer

Hydrogen bonds require more energy to break

Question 9

Which of the following is true about hydrogen bonds?

Accepted Answer

They form between a hydrogen atom and an electronegative atom like oxygen or nitrogen

Question 10

A solution has a pH of $$7. $$Which statement is correct?

Accepted Answer

It is neutral

Question 11

Which of the following best describes the role of valence electrons in chemical bonding?

Accepted Answer

They are responsible for the chemical reactivity and bonding of atoms

Question 12

Which of the following is a consequence of water's polarity?

Accepted Answer

Water can dissolve both polar and ionic substances

Question 13

If a carbon atom forms four single covalent bonds, what is the geometry of the molecule?

Accepted Answer

Tetrahedral

Question 14

Which of the following statements about ionic bonds is correct?

Accepted Answer

They result from the transfer of electrons from one atom to another

Question 15

Which property of water is most important for temperature regulation in living organisms?

Accepted Answer

High specific heat

Question 16

What happens to the hydrogen bonds in water when it evaporates?

Accepted Answer

They are broken as water molecules escape into the air

Question 17

Which of the following best explains why salt (NaCl) dissolves easily in water?

Accepted Answer

Water's partial charges attract the positive and negative ions, separating them

Question 18

Which equation correctly represents the formation of a hydronium ion in water?

Accepted Answer

$$H_2O + H^+ \rightarrow H_3O^+$$

Question 19

Which of the following is NOT a result of hydrogen bonding in water?

Accepted Answer

Water molecules repelling each other

Question 20

A solution has a pH of $$2. $$Which statement is correct?

Accepted Answer

It is acidic and has more $$H^+$$ ions than $$OH^-$$ ions

Water and Carbon: The Chemical Basis of Life – Study Notes

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