CHE1501 ASSIGNMENT 2 SEM1 2021(Latest tutorial letter)

CHE1501

ASSIGNMENT 2 2021

QUESTION 1


𝐶2 𝐻6 + 5𝑂2 → 3𝐻2 𝑂 + 2𝐶𝑂2 𝐶𝑜𝑚𝑏𝑢𝑠𝑡𝑖𝑜𝑛 𝑟𝑒𝑎𝑐𝑡𝑖𝑜𝑛

ANSWER:[4]



QUESTION 2


𝐵𝑎𝑙𝑎𝑛𝑐𝑒𝑑 𝑐ℎ𝑒𝑚𝑖𝑐𝑎𝑙 𝑒𝑞𝑢𝑎𝑡𝑖𝑜𝑛:

2𝐴𝑔𝑁𝑂3 + 𝐶𝑎𝐶𝑙2 → 2𝐴𝑔𝐶𝑙 + 𝐶𝑎(𝑁𝑂3 )2

ANSWER:[4]



QUESTION 3


𝐴𝑐𝑖𝑑 𝑏𝑎𝑠𝑒 𝑟𝑒𝑎𝑐𝑡𝑖𝑜𝑛:

𝐻𝑦𝑑𝑟𝑜𝑐ℎ𝑙𝑜𝑟𝑖𝑐 𝑎𝑐𝑖𝑑 + 𝑐𝑎𝑙𝑐𝑖𝑢𝑚 ℎ𝑦𝑑𝑟𝑜𝑥𝑖𝑑𝑒 → 𝑐𝑎𝑙𝑐𝑖𝑢𝑚 𝑐ℎ𝑙𝑜𝑟𝑖𝑑𝑒 + 𝑤𝑎𝑡𝑒𝑟

𝑃𝑟𝑜𝑑𝑢𝑐𝑡𝑠 = 𝑐𝑎𝑙𝑐𝑖𝑢𝑚 𝑐ℎ𝑙𝑜𝑟𝑖𝑑𝑒 𝑎𝑛𝑑 𝑤𝑎𝑡𝑒𝑟

ANSWER:[2]



QUESTION 4


𝑂𝑣𝑒𝑟𝑎𝑙𝑙 𝑜𝑥𝑖𝑑𝑎𝑡𝑖𝑜𝑛 𝑛𝑢𝑚𝑏𝑒𝑟 = 𝑛𝑒𝑡 𝑐ℎ𝑎𝑟𝑔𝑒 𝑜𝑛 𝑡ℎ𝑒 𝑐𝑜𝑚𝑝𝑜𝑢𝑛𝑑, 𝑒𝑙𝑒𝑚𝑒𝑛𝑡 𝑜𝑟 𝑖𝑜𝑛

𝑎𝑛𝑑 𝑎𝑙𝑠𝑜:

𝑂𝑣𝑒𝑟𝑎𝑙𝑙 𝑜𝑥𝑖𝑑𝑎𝑡𝑖𝑜𝑛 𝑛𝑢𝑚𝑏𝑒𝑟 = 𝑠𝑢𝑚 𝑜𝑓 𝑜𝑥𝑖𝑑𝑎𝑡𝑖𝑜𝑛 𝑛𝑢𝑚𝑏𝑒𝑟 𝑜𝑓 𝑒𝑎𝑐ℎ 𝑒𝑙𝑒𝑚𝑒𝑛𝑡 𝑚𝑎𝑘𝑖𝑛𝑔 𝑡ℎ𝑒 𝑠𝑝𝑖𝑐𝑖𝑒𝑠

𝐿𝑒𝑡: 𝑜𝑥𝑖𝑑𝑎𝑡𝑖𝑜𝑛 𝑛𝑢𝑚𝑏𝑒𝑟 𝑜𝑓 𝐻 = 𝑥

,𝑜𝑥𝑖𝑑𝑎𝑡𝑖𝑜𝑛 𝑛𝑢𝑚𝑏𝑒𝑟 𝑜𝑓 𝐶𝑎 = +2 (𝐺𝑟𝑜𝑢𝑝 2 𝑒𝑙𝑒𝑚𝑒𝑛𝑡)

𝑜𝑥𝑖𝑑𝑎𝑡𝑖𝑜𝑛 𝑛𝑢𝑚𝑏𝑒𝑟 𝑜𝑓 𝐶𝑎 + 2(𝑜𝑥𝑖𝑑𝑎𝑡𝑖𝑜𝑛 𝑛𝑢𝑚𝑏𝑒𝑟 𝑜𝑓 𝐻) = 𝑛𝑒𝑡 𝑐ℎ𝑎𝑟𝑔𝑒 𝑜𝑛 𝑡ℎ𝑒 𝑐𝑜𝑚𝑝𝑜𝑢𝑛𝑑

2 + 2(𝑥) = 0

2𝑥 = −2

𝑥 = −1

𝑜𝑥𝑖𝑑𝑎𝑡𝑖𝑜𝑛 𝑛𝑢𝑚𝑏𝑒𝑟 𝑜𝑓 𝐻 = −1

ANSWER:[2]



QUESTION 5


∗ 𝑂𝑥𝑖𝑑𝑎𝑡𝑖𝑜𝑛 𝑛𝑢𝑚𝑏𝑒𝑟 𝑜𝑓 𝐻 𝑖𝑠 𝑢𝑠𝑢𝑎𝑙𝑙𝑦 + 1 𝑒𝑥𝑐𝑒𝑝𝑡 𝑖𝑛 𝑚𝑒𝑡𝑎𝑙 ℎ𝑦𝑑𝑟𝑖𝑑𝑒𝑠

∗ 𝑂𝑥𝑖𝑑𝑎𝑡𝑖𝑜𝑛 𝑠𝑡𝑎𝑡𝑒 𝑜𝑓 𝑂 𝑖𝑠 𝑢𝑠𝑢𝑎𝑙𝑙𝑦 − 2 𝑒𝑥𝑐𝑒𝑝𝑡𝑠 𝑖𝑛 𝑝𝑒𝑟𝑜𝑥𝑖𝑑𝑒𝑠

𝐿𝑒𝑡: 𝑂𝑥𝑖𝑑𝑎𝑡𝑖𝑜𝑛 𝑛𝑢𝑚𝑏𝑒𝑟 𝑜𝑓 𝑀𝑛 = 𝑥

𝑂𝑥𝑖𝑑𝑎𝑡𝑖𝑜𝑛 𝑛𝑢𝑚𝑏𝑒𝑟 𝑜𝑓 𝑁𝐻4 + = +1

𝑂𝑥𝑖𝑑𝑎𝑡𝑖𝑜𝑛 𝑛𝑢𝑚𝑏𝑒𝑟 𝑜𝑓 𝑂 = −2

2(𝑂𝑥𝑖𝑑𝑎𝑡𝑖𝑜𝑛 𝑛𝑢𝑚𝑏𝑒𝑟 𝑜𝑓 𝑁𝐻4 + ) + 𝑂𝑥𝑖𝑑𝑎𝑡𝑖𝑜𝑛 𝑛𝑢𝑚𝑏𝑒𝑟 𝑜𝑓 𝑀𝑛 + 4(𝑂𝑥𝑖𝑑𝑎𝑡𝑖𝑜𝑛 𝑛𝑢𝑚𝑏𝑒𝑟 𝑜𝑓 𝑂) = 0

2(+1) + 𝑥 + 4(−2) = 0

𝑥 = −2 + 8 = +6

𝑂𝑥𝑖𝑑𝑎𝑡𝑖𝑜𝑛 𝑛𝑢𝑚𝑏𝑒𝑟 𝑜𝑓 𝑀𝑛 = +6

ANSWER:[4]



QUESTION 6



𝐿𝑒𝑡: 𝑂𝑥𝑖𝑑𝑎𝑡𝑖𝑜𝑛 𝑛𝑢𝑚𝑏𝑒𝑟 𝑜𝑓 𝑃 = 𝑥

𝑂𝑥𝑖𝑑𝑎𝑡𝑖𝑜𝑛 𝑛𝑢𝑚𝑏𝑒𝑟 𝑜𝑓 𝐾 = +1 (𝐺𝑟𝑜𝑢𝑝 1 𝑒𝑙𝑒𝑚𝑒𝑛𝑡)

𝑂𝑥𝑖𝑑𝑎𝑡𝑖𝑜𝑛 𝑛𝑢𝑚𝑏𝑒𝑟 𝑜𝑓 𝐻 = +1

𝑂𝑥𝑖𝑑𝑎𝑡𝑖𝑜𝑛 𝑛𝑢𝑚𝑏𝑒𝑟 𝑜𝑓 𝑂 = −2

, 𝑂𝑥𝑖𝑑𝑎𝑡𝑖𝑜𝑛 𝑛𝑢𝑚𝑏𝑒𝑟 𝑜𝑓 𝐾 + 2(𝑂𝑥𝑖𝑑𝑎𝑡𝑖𝑜𝑛 𝑛𝑢𝑚𝑏𝑒𝑟 𝑜𝑓 𝐻) + 𝑂𝑥𝑖𝑑𝑎𝑡𝑖𝑜𝑛 𝑛𝑢𝑚𝑏𝑒𝑟 𝑜𝑓 𝑃

+4(𝑂𝑥𝑖𝑑𝑎𝑡𝑖𝑜𝑛 𝑛𝑢𝑚𝑏𝑒𝑟 𝑜𝑓 𝑂) = 0

1 + 2(+1) + 𝑥 + 4(−2) = 0

1+2+𝑥−8=0

𝑥−5=0

𝑥 = +5

𝑂𝑥𝑖𝑑𝑎𝑡𝑖𝑜𝑛 𝑛𝑢𝑚𝑏𝑒𝑟 𝑜𝑓 𝑃 = +5

ANSWER:[4]



QUESTION 7


∗ 𝑂𝑥𝑖𝑑𝑖𝑧𝑖𝑛𝑔 𝑎𝑔𝑒𝑛𝑡 𝑎𝑙𝑤𝑎𝑦𝑠 𝑔𝑎𝑖𝑛𝑠 𝑒𝑙𝑒𝑐𝑡𝑟𝑜𝑛𝑠 𝑎𝑛𝑑 𝑖𝑠 𝑟𝑒𝑑𝑢𝑐𝑒𝑑

ANSWER:[4]



QUESTION 8
ANSWER:[4]



QUESTION 9


𝐿𝑒𝑡: 𝑜𝑥𝑖𝑑𝑎𝑡𝑖𝑜𝑛 𝑛𝑢𝑚𝑏𝑒𝑟 𝑜𝑓 𝑀𝑛 𝑖𝑛 𝐾𝑀𝑛𝑂4 = 𝑥

𝑜𝑥𝑖𝑑𝑎𝑡𝑖𝑜𝑛 𝑛𝑢𝑚𝑏𝑒𝑟 𝑜𝑓 𝐾 = +1

𝑜𝑥𝑖𝑑𝑎𝑡𝑖𝑜𝑛 𝑛𝑢𝑚𝑏𝑒𝑟 𝑜𝑓 𝑂 = −2

1 + 𝑥 + 4(−2) = 0

𝑥+1−8=0

𝑥 = +7



𝐿𝑒𝑡: 𝑜𝑥𝑖𝑑𝑎𝑡𝑖𝑜𝑛 𝑛𝑢𝑚𝑏𝑒𝑟 𝑜𝑓 𝑀𝑛 𝑖𝑛 𝑀𝑛𝑆𝑂4 = 𝑦

𝑦 + (−2) = 0

𝑦 = +2