1 / 18

Solutions of acids & bases

Solutions of acids & bases. Chemistry – Grade 9. Prepared by the teacher: Ronak Ahmed Duhok International School 2012-2013. If you eat large amounts of foods….!!. You’ll have a terrible case of indigestion. If you had an upset stomach, you’ll fell a stomach ache. Antacids may help you.

zander
Download Presentation

Solutions of acids & bases

An Image/Link below is provided (as is) to download presentation Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript

  1. Solutions of acids & bases Chemistry – Grade 9 Prepared by the teacher: Ronak Ahmed Duhok International School 2012-2013

  2. If you eat large amounts of foods….!!

  3. You’ll have a terrible case of indigestion If you had an upset stomach, you’ll fell a stomach ache. Antacids may help you

  4. How antacid is working? • Antacid: is a weak base that neutralizes a strong acid in your stomach.

  5. Strengths of Acids & Bases • Acids & bases can be strong or weak. The strength of an acid or a base is not the same as the concentration of an acid or base. The strength of an acid or base Depends on the number of molecules that break apart when the acid or base is dissolved in water. The concentration of an acid or a base is the amount of acid or base dissolved in water.

  6. Strong acids & Weak Acids As an acid dissolves in water, the acid’s molecules break apart and produce hydrogen ions, (H+). When an Acid is strong or weak? Strong acid Weak acid If all of the molecules of an acid break apart If only a few molecules of an acid break apart Sulfuric acid H2SO4 Car battery Acetic acid (HC2H3O2) vinegar Nitric acid HNO3 fertilizers Hydrochloric acid HCl stomach Citric acid (lemons) C6H8O7 Carbonic acid (soft drink) H2CO3

  7. Strong Bases & Weak Bases Strong base Weak base When all molecules of a base break apart in water to produce hydroxide ions (OH-) If only a few molecules of a base break apart Aluminum hydroxide Al(OH)3 Antacid Sodium hydroxide NaOH Soap Calcium hydroxide Ca(OH)2 Cement Ammonium hydroxide NH4OH Cleaners Potassium hydroxide KOH Battery electrolyte

  8. Neutralization When the base in an antacid meets stomach acid, a reaction occurs. Neutralization: is the reaction between acids and base. Why Acids & Bases neutralizing one another? Hydrogen ions (H+) In acid Hydroxide ions (OH-) In base react Neutral H2O Other ions from the acid and base dissolved in the water. when the water evaporates, these ions join to form a compound called a salt.

  9. The pH Scale An indicator such as litmus, can identify whether a solution contains an acid or base. Acid base The pH of a solution is a measure of the hydronium ion concentration in the solution.

  10. The solution is neither acidic nor basic • Solution PH =7neutral • Distilled water has a pH of 7. • Basic solutions pH = > 7. • Acidic solutions pH= < 7.

  11. Use of indicators to determine pH It can be used to find out how basic or how acidic a solution is. what is the role of combination of indicators? This can be done if the colors of the indicators are known at different pH value.

  12. How the pH Indicator is working? • The strips of pH paper contain several different indicators. • These strips were dipped into two different solutions. • The pH of each solution is found by comparing the colors on each strip with the color of indicator scale provided. Video Where this kind of indicator is used? It is often used to test the pH of water in pools and aquariums.

  13. pH meter • Is another way to find the pH of a solution. • These pH meters can detect and measure hydronium ion concentration electronically. video

  14. pH and the Environment Prefer acidic soil, pH (4-6) • Living things depend on having a steady pH in their environment. Need basic soil, pH (8-9)

  15. Plants may also have different traits under different growing condition! • Ex: The color of hydrangea flowers varies when the flowers are grown in soils that have different pH values.

  16. Many organisms living in lakes and streams need a neutral pH to survive. • Most rain has a pH between (5.5 and 6). When the rain is acidic and how? When rainwater reacts with compounds found in air pollution, acids are formed and the rain water’s pH decrease. Most acid rain has a pH between (4 and 4.5).

  17. Salts What will be produced if an acid neutralize a base? A salt and water will be produced • An ionic compound that forms when a metal atom replaces the hydrogen of an acid. Salts Table salt is only one example of a large group of compounds that called salt

  18. Uses of Salts Salts have many uses in industry and in homes. • Sodium chloride used in foods its also used to make other compounds, including sodium hydroxide, soap& sodium hydrogen carbonate. • Ammonium nitrate is a salt used to make fertilizers. • Calcium sulfate is used to make wallboard (used in construction).

More Related