Grade 8: Science: Chapter 5: Section 4

Chemists use the ____________ to express the concentration of hydrogen ions in solution.

pH scale

An acid produces ____________ ions in water.

hydrogen

In a neutralization reaction what do bases and acids have?

- Bases have (OH-) - Acids have (H+)

What ion will all these produc when they dissolve in water?

Hydrogen ion

A base produces ____________ ions in water.

Hydroxide

How does hydrogen atom become a hydrogen ion?

It loses an electron and has a positive charge.

Do all bases contian hydroxide ions?

No, bases such as ammonia and calcium oxide do not contains OH-

Is the pH of an acid-base neutralization always 7?

No, it could be close to 7 because one might be a little more acidic or basic.

In water, acids produce ____________ and bases produce ____________.

- hydrogen ions(H+) - hydroxide ions(OH-)

What levels of the pH scale are acidic, neutral and basic?

0-6.9 are acidic, 7 is neutral, and 7.1-14 is basic

Hydroxide ion (OH-)

A negatively charged ion(OH-) made of oxygen and hydrogen

Hydrogen ion (H+)

A positively charged ion(H+) formed of a hydrogen atom that lost its electron

pH scale

A range of values used to indicate how acidic or basic a substance is; expresses the concentration of hydrogen ions in a solution

Neutralization

A reaction of an acid with a base, yielding a solution that is not as acidic or basic as the starting solution were

Can you dilute solution of a strong acid? A concentration of a weak acid?

A small amount of strong acid dissolved in water produces a dilute solution with lots of ions in it. A large amount of weak acid dissolved in water would produce a concentrated solution with very few ions.

What is the difference between a strong acid and a weak acid?

A strong acid dissociate to form hydrogen ions in solution.

What is the definition of an acid?

A substance that produces hydrogen ions in water

What is the definition of a base?

A substance that produces hydroxide ions in water.

What type of solution has a pH of 0-6.9? A) Acidic B) Basic C) Neutral

A) Acidic

Salt A) Ionic compound that can form from the reaction of an acid with a base. B) Reaction between an acid and base. C) H+ D) Series of numbers that indicated the concentration of hydrogen ions in solution E) OH-

A) Ionic compound that can form from the reaction of an acid with a base.

The negative ion found in bases is the A) hydroxide ion B) hydrogen ion C) carbonate ion D) water ion

A) hydroxide ion

Substance with a pH 0-6 is

Acidic

What is neutralization?

Acidic and basic solutions mix together and produce a more nuetral soltuion

Salt

An ionic compound made from the neutralization of acidic with a base

What type of solution has a pH of 7.1-14? A) Acidic B) Basic C) Neutral

B) Basic

Neutralization A) Ionic compound that can form from the reaction of an acid with a base. B) Reaction between an acid and base. C) H+ D) Series of numbers that indicated the concentration of hydrogen ions in solution E) OH-

B) Reaction between an acid and base.

Substances with pH values close to 14 are stong ____________.

Bases

Substance with a pH 8-14 is

Basic

How is the scientific meaning of salt different from the common meaning of salt?

Scientific meaning of salt refers to a specific group of compounds. The common meaning of salt is the stuff you sprinkle on food.

Solution A has a pH of 1.6. Solution B has a pH level of 4. Which solution has a greater concentration of hydrogen ions? Explain.

Solution A because the lower the pH level means the greater concentration of hydrogen ions.

What does the strength of an acid refers to? What does concentration refer to?

Strength refers to how well the acid seperate, into ions in water. How mush solute is dissolved in a given amount of solution

What is the difference between a strong base and a weak base?

Strong bases readily produce hydroxide ions in water. Weak don't produce hydroxide ions in water.

What is the pH of a neutral solution?

The pH of a neutral solution is around 7.

Consider the following list of acids: NHO₃, HF and H₃PO₄

These elements contains hydrogen

What are the products formed when a base reacts with an acid?

When acidic and basic solutions are mixed together, they produce a more neutral solution.

Why are these substance considered bases?

When they dissolve in water, they react with the water to form OH-

What ion will all these bases produce when they dissolve in water?

hydroxide ions OH-

A solution with a pH of 2 is ____________ acidic than a solution with a pH of 6.

more

What is the hydroxide ions made of?

oxygen and hydrogen

Hydrogen Ion A) Ionic compound that can form from the reaction of an acid with a base. B) Reaction between an acid and base. C) H+ D) Series of numbers that indicated the concentration of hydrogen ions in solution E) OH-

C) H+

Which of the following substances is NOT an acid? A) HCI B) H₂SO₄ C) NAOH D) HNO₃

C) NAOH

What type of solution has a pH of 7? A) Acidic B) Basic C) Neutral

C) Neutral

What does a low pH number indicate about the concentrations of hydrogen ions and hydroxide ions?

Concentration of hydrogen ion is high and the concentration of hydroxide ion is low.

What does a high pH indicates about the concentrations of hydrogen ions and hydroxide ions?

Concentration of hydrogen ion is low and the concentration of hydroxide ion is high. (H+) is low (OH-) is high

What are Hydrogen ion (H+) responsible for?

Corroding with metals and turning blue litmus paper red.

Consider the folloiwing a list of bases: (Mg(OH)₂), (Ba(OH)₂) and (CsOH).

OH- or hydroxide ions.

A strip of blue litmus paper placed in a beaker of vinegar will turn ____________.

Red

Which of the following statements in NOT true about neutralization? A) An acid and base are the reactants. B) A salt and water are the products. C) There is no color in litmus paper when the reaction is over. D) It produces an acid-base mixture that is more acidic than both the individual starting solutions.

D) It produces an acid-base mixture that is more acidic than both the individual starting solutions.

pH scale A) Ionic compound that can form from the reaction of an acid with a base. B) Reaction between an acid and base. C) H+ D) Series of numbers that indicated the concentration of hydrogen ions in solution E) OH-

D) Series of numbers that indicated the concentration of hydrogen ions in solution

Hydroxide ion A) Ionic compound that can form from the reaction of an acid with a base. B) Reaction between an acid and base. C) H+ D) Series of numbers that indicated the concentration of hydrogen ions in solution E) OH-

E) OH-

Estimate the pH of a mixture of a large amount of weak acid and large amount of strong base.

pH level would be around 9 because the pH level of the base would be higher than the acid.

Which solution has the greater concentration of hydrogen ions (H+), a solution with a pH of 3 or one with a pH of 7?

pH of 3 has the greater concentration of hydrogen ions because the lower end of the scale is more acidic.

A neutralization reaction produces

salt and water