Sodium ions: Difference between revisions
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=== Definition and electronic structure === | === Definition and electronic structure === | ||
A sodium [[Atom|atom]] that has lost an [[Electron|electron]] becomes the monatomic charged sodium [[Ions|ion]] and is denoted by the symbol Na<sup>+</sup>. Sodium ions have the electronic structure<ref name="Electronic structure of ions">Chemguide. Electronic Structures Of Ions. 2012 [cited 30/11/2016]. Available from: http://www.chemguide.co.uk/atoms/properties/ionstruct.html</ref> 1s<sup></sup><sup>2</sup>2s<sup>2</sup>2p<sup>6</sup>, as they have become [[Oxidation|oxidised]], having lost the lone electron in its 3s subshell: this is why sodium ions have a +1 charge overall.<br> | A sodium [[Atom|atom]] that has lost an [[Electron|electron]] becomes the monatomic charged sodium [[Ions|ion]] and is denoted by the symbol Na<sup>+</sup>. Sodium ions have the electronic structure<ref name="Electronic structure of ions">Chemguide. Electronic Structures Of Ions. 2012 [cited 30/11/2016]. Available from: http://www.chemguide.co.uk/atoms/properties/ionstruct.html</ref> 1s<sup></sup><sup>2</sup>2s<sup>2</sup>2p<sup>6</sup>, as they have become [[Oxidation|oxidised]], having lost the lone electron in its 3s subshell: this is why sodium ions have a +1 charge overall.<br> | ||
=== Sodium ions in the human body === | === Sodium ions in the human body === | ||
Sodium ions are present in the human body playing key roles in several processes, such as in the primary [[Active Transport|active transport]] carried out by the [[Sodium-potassium pump|Na<sup>+</sup>/K<sup>+</sup>-ATPase]]<ref name="The sodium-potassium pump and active transport in relation to action potentials">Georgia State University, HyperPhysics. The Sodium-Potassium Pump. Published: N/A [cited 30/11/2016]. Available from: http://hyperphysics.phy-astr.gsu.edu/hbase/Biology/nakpump.html</ref>, during the [[Depolarisation|depolarisation]] of neuronal [[Cell membrane|cell membranes]] during an [[Action potential|action potential]] and as an important component in the [[Secondary active transport|secondary active transport]] of [[Glucose|glucose]] which is completed by the [[Sodium-glucose symporter|Na<sup>+</sup>-glucose]] [[Symporter|symporter]].<br> | Sodium ions are present in the human body playing key roles in several processes, such as in the primary [[Active Transport|active transport]] carried out by the [[Sodium-potassium pump|Na<sup>+</sup>/K<sup>+</sup>-ATPase]]<ref name="The sodium-potassium pump and active transport in relation to action potentials">Georgia State University, HyperPhysics. The Sodium-Potassium Pump. Published: N/A [cited 30/11/2016]. Available from: http://hyperphysics.phy-astr.gsu.edu/hbase/Biology/nakpump.html</ref>, during the [[Depolarisation|depolarisation]] of neuronal [[Cell membrane|cell membranes]] during an [[Action potential|action potential]] and as an important component in the [[Secondary active transport|secondary active transport]] of [[Glucose|glucose]] which is completed by the [[Sodium-glucose symporter|Na<sup>+</sup>-glucose]] [[Symporter|symporter]]. <br> | ||
When a stimulus causes membrane potential to rise from its resting potential of -70mV to threshold frequency of -55mV it causes the voltage gated sodium channels to open allowing the flow of sodium ions into the cell resulting in depolarisation. Once the neurone reaches peak polarisation the sodium channels close and the potassium channels open allowing the flow of potassium ions out of the cell – this is called repolarization. During repolarisation, too many potassium ions move out of the cell causing the membrane potential to fall too low therefore resulting in hyperpolarisation. When hyperpolarisation occurs, the membrane must restore the potential back to its resting potential by transporting 3 Na+ out of the cell and 2K+ into the cell via the sodium potassium pump using ATP<ref>Hyper Physics, Ka Xiong Charand, http://hyperphysics.phy-astr.gsu.edu/hbase/Biology/actpot.html</ref>. <br> | |||
Sodium ions also form ionic compounds with negative ions, a common example being the neutral ionic compound [[Sodium chloride|sodium chloride]] (NaCl), where the sodium ion has a positive +1 charge (Na<sup>+</sup>) and the chloride ion has a negative -1 charge (Cl<sup>-1</sup>).<br> | === In compounds === | ||
Sodium ions also form ionic compounds with negative ions, a common example being the neutral ionic compound [[Sodium chloride|sodium chloride]] (NaCl), where the sodium ion has a positive +1 charge (Na<sup>+</sup>) and the chloride ion has a negative -1 charge (Cl<sup>-1</sup>).<br> | |||
=== '''References:''' === | === '''References:''' === | ||
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Revision as of 12:10, 5 December 2016
Definition and electronic structure
A sodium atom that has lost an electron becomes the monatomic charged sodium ion and is denoted by the symbol Na+. Sodium ions have the electronic structure[1] 1s22s22p6, as they have become oxidised, having lost the lone electron in its 3s subshell: this is why sodium ions have a +1 charge overall.
Sodium ions in the human body
Sodium ions are present in the human body playing key roles in several processes, such as in the primary active transport carried out by the Na+/K+-ATPase[2], during the depolarisation of neuronal cell membranes during an action potential and as an important component in the secondary active transport of glucose which is completed by the Na+-glucose symporter.
When a stimulus causes membrane potential to rise from its resting potential of -70mV to threshold frequency of -55mV it causes the voltage gated sodium channels to open allowing the flow of sodium ions into the cell resulting in depolarisation. Once the neurone reaches peak polarisation the sodium channels close and the potassium channels open allowing the flow of potassium ions out of the cell – this is called repolarization. During repolarisation, too many potassium ions move out of the cell causing the membrane potential to fall too low therefore resulting in hyperpolarisation. When hyperpolarisation occurs, the membrane must restore the potential back to its resting potential by transporting 3 Na+ out of the cell and 2K+ into the cell via the sodium potassium pump using ATP[3].
In compounds
Sodium ions also form ionic compounds with negative ions, a common example being the neutral ionic compound sodium chloride (NaCl), where the sodium ion has a positive +1 charge (Na+) and the chloride ion has a negative -1 charge (Cl-1).
References:
- ↑ Chemguide. Electronic Structures Of Ions. 2012 [cited 30/11/2016]. Available from: http://www.chemguide.co.uk/atoms/properties/ionstruct.html
- ↑ Georgia State University, HyperPhysics. The Sodium-Potassium Pump. Published: N/A [cited 30/11/2016]. Available from: http://hyperphysics.phy-astr.gsu.edu/hbase/Biology/nakpump.html
- ↑ Hyper Physics, Ka Xiong Charand, http://hyperphysics.phy-astr.gsu.edu/hbase/Biology/actpot.html