| Author | Message | ||
     981005 Username: 981005 Registered: 04-2003 |
1)NaOH 2)Ca(OH)2 3)Pb(OH)2 4)Ag(OH)2 5)NH4OH 仲有,有冇d oxide係soluble in water架? | ||
| 981005 Username: 981005 Registered: 04-2003 |
仲有...形容chlorine果陣味叫咩? 唔記得左邊隻有bad-egg smell. 唔該recall番我d memories T.T thx!! | ||
| Chio U Kim Username: cuk Registered: 04-2003 |
Ag(OH)2 and NH4OH do not exist. CO2, NO2 and SO2 are soluble oxides of non-metals. K2O, Na2O and CaO are soluble oxides of metals. Chlorine gas smells like a bleach or chlorine has a pungent/irritating/unpleasant smell. Hydrogen sulphide, H2S has a bad egg smell. | ||
| 981005 Username: 981005 Registered: 04-2003 |
趙sir! acid salt 即係邊d呀? strong acid(HCl)同weak alkali(NH3) 出既salt(NH4Cl) 係唔係acid salt? 濃H2SO4+NaNO3-->NaHSO4 + HNO3 NaHSO4 係唔係都係acid salt? NaHCO3又係唔係? 係唔係仲有H既salt就一定係acid salt? 而NH4同Cl comine左之後, 我記得你上堂講過..Cl令到隻salt好酸,而NH4 令佢微alkali, 結果隻salt 就變微酸,係唔係咁? | ||
| 981005 Username: 981005 Registered: 04-2003 |
繼頭先個問題, H2SO4 + NaNO3 咪會出 NaHSO4 + HNO3 既... 咁H2SO4 + 2NaNO3 -->2HNO3 +Na2SO4 哩條式會唔會發生? 另外2HNO3 +Na2SO4 -->H2SO4 + 2NaNO3 哩條r式又會唔會發生? 我係度諗如果2條都發生,咁咪冇止境咁reversible? 我估係其中一條唔得 or 2條都唔得.. so complex...>< | ||
| 981005 Username: 981005 Registered: 04-2003 |
syllbus入面係咪得 displacement reaction係 salt react到? | ||
| 981005 Username: 981005 Registered: 04-2003 |
更正: syllbus入面係咪得 "displacement reaction"同 "salt +con.H2SO4" 係有reaction with salt? | ||
| Chio U Kim Username: cuk Registered: 04-2003 |
Only non-volatile acid (e.g. sulphuric acid)can displace volatile acid(e.g. nitric acid or hydrochloric acid) from its salts. NH4Cl is acidic when dissolved in water but it is not an acid salt. An acid salt is formed by incomplete neutralization of a dibasic/tribasic acid. (Monobasic acids cannot give acid salts.) An acid salt should have at least one hydrogen atom per unit that can be released as a hydrogen ion in water. |