Experimental activity chemistry VIII th gradeExperimental activity chemistry VIII th grade

Study acidsStudy acidsCChemical hemical ppropertiesroperties

Acids not color phenolphthalein

Acids turn red litmus solution

2HCl + Zn = ZnCl2HCl + Zn = ZnCl22 + H + H22↑ ↑

Hydrogen gas is released. The lights, a phenomenon accompanied by a click.

CuO + HCl = CuClCuO + HCl = CuCl22 + H + H22O O

CuO + HCuO + H22SOSO44 = CuSO = CuSO44 + H + H22OO

When adding phenolphthalein over natrium hydroxide solution, it turns red. Bleaching solution from adding acid to a neutral transition point.

Neutralization.

H2SO4 + 2NaOH = Na2SO4 + 2H2O HCl + NaOH = NaCl + H2O

- exchange reactions

HCl + AgNO3 = AgCl↓ + HNO3

- exchange reactions;-cheesy white precipitate formed, AgCl, silver chloride, photosenzitive;

H2SO4 + BaCl2 = BaSO4↓+ 2HCl - exchange reactions

No. Explication of phenomena. Conclusions Importance and uses of acids

1. Acids turn red litmus solution and not color phenolphthalein.

The recognition of acid

2. Acids react with metals more reactive than hydrogen.Salts and hydrogen are obtained.Hydrogen is emitted and by lightning produces a phenomenon accompanied by a click. 2HCl + Zn = ZnCl2 + H2↑ H2SO4 + Zn = ZnSO4 + H2↑ - substitution reactions.

- obtaining salts - obtaining hydrogen in laboratory

3. Acids react with metal oxides. Form salts and water. CuO + HCl = CuCl2 + H2OCuO + H2SO4 = CuSO4 + H2O-exchange reactions

-obtaining salts -leaching of copper oxide on the surface of objects to be soldered

4. Acids react with hydroxides. Form salts and water. Reaction of acidsand hydroxides is called neutralization. Reaction is produced releasing heat. H2SO4 + 2NaOH = Na2SO4 + 2H2O HCl + NaOH = NaCl + H2O- exchange reactions

-obtaining salts - neutralization of acids and bases

5. HCl + AgNO3 = AgCl↓ + HNO3

- exchange reactions;-cheesy white precipitate formed, AgCl, silver chloride, photosenzitive;

H2SO4 + BaCl2 = BaSO4↓+ 2HCl exchange reactions

Acids react with carbonates with effervescence.It emits carbon dioxide. Not support combustion.2HCl + Ca CO3 = Ca Cl2 + H2O + CO2↑

- recognition of hydrochloric acid and soluble chlorides

- recognition of soluble sulfates and sulfuric acid

- recognition of carbonate;preparation of carbon dioxide in the laboratory.

HH22SOSO44

laboratory reagenlaboratory reagentt

chemical chemical fertilizersfertilizers

accumulatorsaccumulators

detergentsdetergents

paints and paints and varnishesvarnishes

oxidizingoxidizing

plasticsplastics

UsesUses H H22SOSO44

HCl

laboratory reagent

laboratory reagent

cleaning metals

cleaning metals

medicinesmedicines

plasticsplastics

chloride productionchloride production

solventssolvents

dyesdyes

production of gelatine

UUsing HClsing HCl