[DSE化學2018]同學準備好DSE CHEM未? (3)

Diaphragm cell out-c?
書搵唔到

yes 2016開始cut左

homogeneous heterogeneous catalyst 係咪out咗syll架喇

yes

可唔可以講下2012 q8 唔係好明c(ii) d(i)

If the question asks to find the number of mole of oxygen in MgO
Suppose i calculated the mass of oxygen in it is k gram
Mole of oxygen = k/16 or k/32 ?
Thx

Then if finding mole of na in Na2O,
Mole of Na = mass of Na found / (23*2)
Is it?

全部都淨係除單粒atom既molar mass
你計緊atom既mole
Na2O
Na mass/23 O mass/16
計出黎會2:1

佢要計返decomposition of KHCO3 kJ mol-1
因爲條式本身係2KHCO3 -> K2CO3 + H2O + CO2
個reaction行一次叫dH(reaction)
除2先係dH(decomposition)

corresponding colour of vanadium, chromium, manganese ,iron in different oxidation state 係咪一定要背晒

common果d要記
vanadium果d正路都比你

thanks

Acetic acid production嗰堆野同reichstein process洗唔洗記

其實之前答左好多次
in chem唔洗記vitamin C / CH3COOH既specific process
佢考有關既野會比曬資料你 例如2015
an chem唔洗記specific計數case 佢考會比曬procedure 唔會出d你無見過就唔識計既case
過往幾年考計數都唔係你書有既case黎

thats why我拍片有講叫大家睇syllabus

唔該哂 我揾下你啲片先

COOH嘅carbon計唔計落propanoic acid個3個carbon

死左圖

梗係計

唔關事 佢特登出個你未學過既reaction要你即場推
唔好覺得樣樣野都一定會喺書見過/syllabus講明考邊d

理論上係