Chemistry pg 43 - 51
Acids
Formic acid - bees and ants inject the acid into you and this affects your skin cells and nerves
Citric acid - lemons and grape fruit
Lactic acid - yoghurt
Acetic acid - vinegar
Concentrated sulphuric acid reacts rapidly with paper and cloth
Battery acids react with copper coins
Hydrolic acid reacts with concrete
These acids are corrosive - they corrode or “eat away”
Acids are corrosive since they react chemically and can burn your skin
Safety with acids
Concentrated solutions have a lot of acid and not a lot of water and are very deangerous
Dilute solutions have more water in them and are less dangerous but must be handled with care still
Spill any acid / alkali on clothes , your skin or the bench - wash with lots of water and then call a teacher
Spill acid / alkali on eye - wash it with lots of water for 20mins + blink you’re eyelid under water + tell teacher
Check label on bottle when working with acids - often have a corrosive symbol
Testing for gases
Gas causes glowing splint to relight - oxygen
lit match in gas makes a mini explosion - gas it’s burning in is hydrogen
gas that puts out a burning flame - carbon dioxide
litmus paper (blue and red)
stays / turns blue - base
stays red / turns red - acid
stays same colour - nuetral
hydrochloric + magnesium (cover test tube with thumb) = explosion heard which makes hydrogen gas
hydrochloric acid + marble chips = no explosion and no gas was formed