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
綠裏透紫的光2018-04-20 13:02:16
Then if finding mole of na in Na2O,
Mole of Na = mass of Na found / (23*2)
Is it?
化學艾維斯2018-04-20 13:05:33
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
綠裏透紫的光2018-04-20 13:08:02
化學艾維斯2018-04-20 13:10:03
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)
綠裏透紫的光2018-04-20 13:11:10
corresponding colour of vanadium, chromium, manganese ,iron in different oxidation state 係咪一定要背晒
化學艾維斯2018-04-20 13:11:43
common果d要記
vanadium果d正路都比你
theweeknd2018-04-20 13:31:01
thanks
知知依時2018-04-20 15:46:08
Acetic acid production嗰堆野同reichstein process洗唔洗記
化學艾維斯2018-04-20 15:55:35
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