Tauira Pātai me te Kōrero mō ngā Whakamahinga Hikohiko: Paninga Konganuku
Ko te matū hikohiko he peka o te matū e ako ana i te whanaungatanga i waenga i ngā tauhohenga matū me te iahiko. Ko tētahi o ngā whakamahinga tino noa me te whai hua o te matū hikohiko ko te whakakikorua konganuku, te whakanoho hiko rānei. Ka whakamahia te whakakikorua konganuku i roto i ngā momo ahumahi, mai i te whakapaipai ki te mahi, pērā i te paninga ātete-waikura, te whakapai ake rānei i te kawe hiko.
Ka matapakihia e tēnei tuhinga ētahi tauira raruraru e pā ana ki te whakamahinga o te matū hiko i roto i te whakakikoruatanga whakarewa, me ngā mahi hei whakaoti i aua raruraru. Mā te mārama ki ngā ariā taketake me ngā whakamahinga mahi o te whakanoho hiko ka āwhina i a koe ki te whakaoti i ngā momo raruraru i roto i tēnei mara. Anei ētahi tauira raruraru:
Tauira Raru 1: Te Whakakikorua Hiriwa ki te Parahi
Pātai:
E hiahia ana koe ki te pania he rau parahi ki te hiriwa mā te whakamahi i te wairewa hiriwa nitrate (AgNO3). E 500 karamu te taumaha o te rau parahi, e 2 amps te hiko e whakamahia ana, ā, e 1 hāora te roa o te paninga. E hia karamu hiriwa ka pania ki te rau parahi?
Kōrero:
1. Whakatauhia te Utu Hiko e Whakamahia ana:
Ka taea te tatau i te utu hiko i whakamahia (Q) mā te whakamahi i te tātai:
\[
Q = I \whakanuia ki te t
\]
Kei hea:
– I = iahiko hiko (ampere)
– t = wā (hēkona)
Tahurihia te wā mai i ngā hāora ki ngā hēkona:
\[
t = 1 \text{ hāora} \times 3600 \text{ hēkona/hāora} = 3600 \text{ hēkona}
\]
Te tatau i te utu hiko:
\[
Q = 2 \text{ A} \times 3600 \text{ s} = 7200 \text{ Coulomb}
\]
2. Te Tātai i te Ia Faraday (nF):
Ko te tauhohenga whakakikorua hiriwa o Ag+ ki Ag(s) ko:
\[
\text{Ag}^+ + e^- \rightarrow \text{Ag}
\]
Ko te tikanga o tēnei, e hiahiatia ana te 1 mole o ngā irahiko hei whakatakoto i te 1 mole o te hiriwa.
Ko te uara o te pūmau o Faraday (F) he 96485 Coulombs/mol irahiko.
Te tatau i ngā mole o ngā irahiko e whakamahia ana:
\[
\kāhua{n} = \frac{Q}{F} = \frac{7200 \kāhua{ C}}{96485 \kāhua{ C/mol}} = 0.0746 \kāhua{ mol}
\]
3. Te Tātai i te Papatipu o te Hiriwa Kua Pania:
Mā te whakamahi i te papatipu molar o Ag (107.87 g/mol), ka taea te tatau i te papatipu o te hiriwa penei:
\[
\text{Taumaha o Ag} = 0.0746 \text{ mol} \times 107.87 \text{ g/mol} = 8.05 \text{ g}
\]
Nō reira, ka whakakikoruatia te 8.05 karamu o te hiriwa ki runga i te pepa parahi.
Tauira Pātai 2: Te Whai Hua o te Paninga
Pātai:
Mena i te tukanga whakakikorua hiriwa o mua, ko te pai o te whakakikorua he 85% noa iho, e hia karamu hiriwa i whakakikoruatia ki te pepa parahi?
Kōrero:
1. Te Tātai i te Papatipu o te Hiriwa me te Whai Hua:
Ko te taumaha o te hiriwa whakakikoruatia, me te kore e whakaarohia te whai huatanga, he 8.05 karamu (mai i te tauira pātai 1).
I te 85% o te whai huatanga, ko te taumaha tuturu o te hiriwa whakakikoruatia ko:
\[
\text{Papatipu tuturu o Ag} = 8.05 \text{ g} \times 0.85 = 6.84 \text{ g}
\]
Nō reira, e 6.84 karamu hiriwa kua whakakikoruatia ki runga i te pepa parahi.
Tauira 3: Te paninga i ētahi atu konganuku
Pātai:
Ki te hiahia koe ki te pani i tētahi mea ki te konganuku nikara mā te whakamahi i te wairewa NiSO4, kia pēhea te roa e hiahiatia ana hei pani i te 10 karamu o te nikara mēnā ko te iahiko e whakamahia ana he 3 Āmperes?
Kōrero:
1. Te Whakatau i te Hiahiatanga o te Irahiko Mole:
Ko te tauhohenga whakakikorua nikara o te Ni^2+ ki te Ni(s) ko:
\[
\text{Ni}^{2+} + 2e^- \rightarrow \text{Ni}
\]
Ko te tikanga o tēnei e 2 ngā mole o ngā irahiko e hiahiatia ana hei whakatakoto i te 1 mole o te nikara.
2. Te Tātai i ngā Ira o te Nikara:
Mā te whakamahi i te papatipu molar o te nikara (58.69 g/mol), ko ngā molar o te nikara e hiahiatia ana ko:
\[
\text{n (Ni)} = \frac{10 \text{ g}}{58.69 \text{ g/mol}} = 0.1704 \text{ mol Ni}
\]
3. Te Tātai i ngā Irahiko:
Nā te mea e rua ngā irahiko e hiahiatia ana mō ia ira nikara:
\[
\text{n (ngā irahiko)} = 0.1704 \text{ mol Ni} \times 2 \text{ mol e^-}/\text{mol Ni} = 0.3408 \text{ ngā irahiko mole}
\]
4. Te Tātai i te Utu Hiko:
Mā te whakamahi i te pūmau a Faraday (F = 96485 C/mol), ko te utu hiko e hiahiatia ana ko:
\[
Q = \text{n (irahiko)} \times F = 0.3408 \text{ mol} \times 96485 \text{ C/mol} = 32872 \text{ C}
\]
5. Te Tātai i te Wā e Hiahiatia ana:
Mēnā he 3 Amperes te iahiko (I), ko te wā (t) e hiahiatia ana ko:
\[
t = \frac{Q}{I} = \frac{32872 \text{ C}}{3 \text{ A}} = 10957.33 \text{ hēkona}
\]
Tahurihia ngā hēkona ki ngā hāora:
\[
t = \frac{10957.33 \text{ s}}{3600 \text{ s/haora}} = 3.04 \text{ hāora}
\]
Nō reira, ko te wā e hiahiatia ana hei paninga i te 10 karamu o te nikara he tata ki te 3.04 hāora.
Whakamutunga
I roto i tēnei tuhinga, kua matapakihia e mātou ētahi tauira raruraru e pā ana ki te whakamahinga o te matū hiko i roto i te whakakikoruatanga whakarewa. Mā te mārama ki ngā mahi e whai wāhi ana ki te whakakikoruatanga hiriwa me te nikara, ka taea e koe te mārama ake ki ngā whakamahinga mahi o te matū hiko. Ko ngā tukanga pēnei i te whakatau i te utu hiko e whakamahia ana, te tatau i ngā mole o ngā irahiko me te papatipu o te whakarewa e whakakikoruatia ana, me te whakatau i te wā e hiahiatia ana mō te tukanga whakakikoruatanga he pūkenga matua katoa e hiahiatia ana i roto i tēnei mara.
Ko te tumanako ka whai hua tēnei tuhinga hei āwhina i a koe ki te mōhio ki ngā ariā me ngā tono o te matū hiko i roto i te whakakikorua whakarewa.
