Acids and Alkalis Chemical Reactions PDF

# Acids and Alkalis ## Chemical reactions involving acids and alkalis - Acid + Alkali = (salt + water) heat - Acid + Metal = (salt) + hydrogen - Acid + carbonate = (salt) + CO2 + water ## pH scale: | 0 | 1 | 2 | 3 | 4 | 5 | 6 | 7 | 8 | 9 | 10 | 11 | 12 | 13 | 14 | |---|---|---|---|---|---|---|--...

# Acids and Alkalis ## Chemical reactions involving acids and alkalis - Acid + Alkali = (salt + water) heat - Acid + Metal = (salt) + hydrogen - Acid + carbonate = (salt) + CO2 + water ## pH scale: | 0 | 1 | 2 | 3 | 4 | 5 | 6 | 7 | 8 | 9 | 10 | 11 | 12 | 13 | 14 | |---|---|---|---|---|---|---|---|---|---|---|---|---|---|---| | Battery acid | Stomach acid | Lemon juice | White vinegar | Tomato juice | Black coffee | Soya milk | Water | Human Blood | Hand soap | Laundry detergent | Ammonia cleaner | Liquid bleach | Jif bleach | Strong alkali like drain cleaner | **More red => Acids** **More blue => Alkali** ### Litmus paper: | | Acidic | Alkaline | Neutral | |---|---|---|---| | Blue litmus | Turns red | Stays blue | No change | | Red litmus | Stays red | Turns blue | No change | ### Universal indicator: - No color change, convenient - Less solutions needed - Scalp active measurement - Doesn't work on dark colored solutions - Cannot be reused - Gives inaccurate readings ## pH meter: - Needs calibration - Needs more solution - Works on any coloured solutions - Reusable - With proper calibration, gives very accurate results ## Common Acids: - Sulphuric acid - Hydrochloric acid - Nitric acid ## Formula conversions - Sulphate = Sulphate - Nitric = Nitrate - Hydrochloric = Chloride - When doing equations always list the metal first. - **Acid + Alkali -> Salt + Water** - **Reactants -> Products** - This is the word equation for neutralization. - Bee stings, mosquito bites, and ant bites are acidic - This means alkali can be used to treat it via neutralization - Dilute acids corrode some metals - Hydrogen is produced in this reaction - During neutralization salt and water form whilst releasing thermal energy ### Examples: - Nitric acid + magnesium -> magnesium nitrate + hydrogen - Hydrochloric acid + calcium carbonate -> calcium chloride + CO2 + water - Sulphuric acid + sodium hydroxide -> sodium sulphate + water ## Lab equipment: - Measuring cylinder - Tripod - Bunsen burner - Flame ## Reactions with a burning splint | | | | |---|---|---| | **Oxygen** | **Burning splint** | **Glowing splint** | | Relights (makes flame larger) | Relights flame | | | | Extinguishes flame | | | | Fire goes out completely | | ## Reactions with lime water: | | | | |---|---|---| | **Lime water** | **CO2** | | | No change in colour | White (calcium carbonate) precipitate | | ## First Aid: ### Acids/Alkalis contact: | | Action | |---|---| | **Skin** | Immediately wash affected area and slowly running water for at least 10 minutes | | **Eyes** | Immediately wash affected eye with eyewash bottle for at least 10 minutes | | **Clothes** | Carefully remove the affected clothes and avoid contact between the clothing and any acid/alkali | ## Safety precautions: ### Before : - Wear gloves when handling acids / alkalis - Wear a lab coat and protective goggles - Read hazard symbols to take necessary precautions ### During: - Avoid direct contact with solutions - Do not drink / taste solutions - Fill no more than 1/3 of container - Do not mix solutions without teachers approval. - Handle with care, avoid spilling. ### After: - Pour used solutions into waste bottles. - Do not pour into sink. - Wash hands thoroughly with soap. ## Additional information: - **Marble dissolves in acid.** - **This reaction forms CO2.** - **CO2 is released in the form of gas bubbles.** - **Limestone corrodes under acid.** - **Produces calcium chloride and CO2 gas, which bubbles off the limestone.** - **Zinc can be corroded by both alkalis and acids.** - **If a test tube contains very dilute nitric acid and zinc foil and a burning splint is inserted, a "pop" sound is produced, indicating the presence of hydrogen.** ## Image information: - The image shows a cartoon of a person sitting in a bathroom with a smiley face on the toilet bowl. Above it reads "sigma" and a speech bubble reads "THOSE WHO KNOW". - This is a humorous cartoon that appears to mock those who are unaware of the safety precautions involved in handling acid and alkali. - The image also contains some notes on the bottom which read "Bdkan rage + german staretadronal + nor adrenaline+ Mangoes Mangos Mangoes". - It is unclear what these notes refer to.