A) How are acids and protons related? (1 point)

Question

Acids are substances that contain more protons than bases.
Acids are substances that contain fewer protons than bases.
An acid can accept a proton from a base when they react.
An acid can donate protons to a base when they react.
A) Which statement best describes the difference between a substance with a pH of 3.0 and a
substance with a pH of 6.0? (1 point)
The substance with the higher pH has twice as many hydrogen ions per volume of water.
The substance with the lower pH has 1,000 times as many hydrogen ions per volume of water.
The substance with the lower pH has twice as many hydrogen ions per volume of water.
The substance with the higher pH has 1,000 times as many hydrogen ions per volume of water

Answer 1

A) The correct statement regarding the relationship between acids and protons is: An acid can donate protons to a base when they react.

B) The statement that best describes the difference between a substance with a pH of 3.0 and a substance with a pH of 6.0 is: The substance with the lower pH has 1,000 times as many hydrogen ions per volume of water.

This is because the pH scale is logarithmic, meaning each whole number change on the scale represents a tenfold difference in hydrogen ion concentration. Therefore, a difference of 3 pH units (from pH 3 to pH 6) corresponds to a factor of \(10^3\) or 1,000 times the concentration of hydrogen ions.

Answer 2

A)
Use the reaction to answer the question.
HCl + H O → Cl + H O
Which statement about the reaction is correct?
(1 point)
2
–
3
+
H O is an acid, and Cl is its conjugate base. 2
–
H O is an acid, and H O is its conjugate base. 2 3
+
HCl is an acid, and Cl is its conjugate base. –
HCl is an acid, and H O is its conjugate base. 3
+
A) Which pattern in electronegativity do elements in the periodic table display? (1 point)
Electronegativity is lowest on the left and right sides of the periodic table, and highest in the
middle of a row.
Electronegativity increases from left to right within a row of the periodic table.
Electronegativity is highest on the left and right sides of the periodic table, and lowest in the
middle of a row.
Electronegativity decreases from left to right within a row of the periodic table

Answer 3

A) Regarding the reaction \( \text{HCl} + \text{H}_2\text{O} \rightarrow \text{Cl}^- + \text{H}_3\text{O}^+ \), the correct statement is: HCl is an acid, and Cl\(^-\) is its conjugate base.

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B) The correct statement about the pattern of electronegativity in the periodic table is: Electronegativity increases from left to right within a row of the periodic table.

This means that as you move across a period from left to right, the electronegativity of elements generally increases due to the increasing positive charge in the nucleus, which attracts electrons more strongly.

Answer 4

A) Which option correctly shows the concentration of H O ions in pure water? (1 point) 3
+
7 mol/L
14 mol/L
1.0 × 10 mol/L -7
1.0 x 10 mol/L

Answer 5

The correct option that shows the concentration of \( \text{H}_3\text{O}^+ \) ions (or \( \text{H}^+ \) ions) in pure water is: 1.0 × 10\(^{-7}\) mol/L.

In pure water at 25°C, the concentration of hydrogen ions is indeed approximately \( 1.0 \times 10^{-7} \) mol/L due to the autoionization of water.