QUALITATIVE ANALYSIS - ION IDENTIFICATION

Title:
Carry out procedures to identify ions present in solution
Credits: 3
Assessment: Internal
Date version published: 17 November 2011
This achievement standard involves carrying out procedures to identify ions present in solution.
Achievement Criteria
Achievement
· Carry out procedures to identify ions present in solution.
Achievement with Merit
· Carry out procedures to justify the identification of ions present in solution.
Achievement with Excellence
· Carry out procedures to comprehensively justify the identification of ions present in solution.
Explanatory Notes
1 This achievement standard is derived from The New Zealand Curriculum, Learning Media, Ministry of Education, 2007, Level 7. The standard is aligned to the Nature of Science achievement objectives and the Material World achievement objectives, and is related to the material in the Teaching and Learning Guide for Chemistry, Ministry of Education, 2010 at http://seniorsecondary.tki.org.nz.
2 Procedures outlined in Safety and Science: a Guidance Manual for New Zealand Schools, Learning Media, Ministry of Education, 2000, should be followed.
3 Carry out procedures to identify ions involves collecting primary data and using these observations to identify ions in solution using a procedure provided.
Carry out procedures to justify the identification of ions involves writing balanced equations for all the reactions where precipitates are formed.
Carry out procedures to comprehensively justify the identification of ions involves interpreting observations by recognising the formation of complex ions and writing balanced equations for these reactions.
4 Identification of ions must be supported by experimental observations and identification of all precipitates formed.
5 Ions to be identified will be limited to: Ag+, Al3+, Ba2+, Cu2+, Fe2+, Fe3+, Mg2+, Pb2+, Na+, Zn2+, Cl–, CO32–, I–, NO3–, OH–, SO42–. Na+ and NO3– are identified by a process of elimination.
6 Complex ions are limited to [FeSCN]2+ and those formed when OH–(aq) or NH3(aq) react with cations listed in EN 5 above, ie [Ag(NH3)2]+, [Al(OH)4]–, [Pb(OH)4]2–, [Zn(OH)4]2–, [Zn(NH3)4]2+, [Cu(NH3)4]2+.
7 Conditions of Assessment related to this achievement standard can be found at www.tki.org.nz/e/community/ncea/conditions-assessment.php.
Carry out procedures to identify ions present in solution
Credits: 3
Assessment: Internal
Date version published: 17 November 2011
This achievement standard involves carrying out procedures to identify ions present in solution.
Achievement Criteria
Achievement
· Carry out procedures to identify ions present in solution.
Achievement with Merit
· Carry out procedures to justify the identification of ions present in solution.
Achievement with Excellence
· Carry out procedures to comprehensively justify the identification of ions present in solution.
Explanatory Notes
1 This achievement standard is derived from The New Zealand Curriculum, Learning Media, Ministry of Education, 2007, Level 7. The standard is aligned to the Nature of Science achievement objectives and the Material World achievement objectives, and is related to the material in the Teaching and Learning Guide for Chemistry, Ministry of Education, 2010 at http://seniorsecondary.tki.org.nz.
2 Procedures outlined in Safety and Science: a Guidance Manual for New Zealand Schools, Learning Media, Ministry of Education, 2000, should be followed.
3 Carry out procedures to identify ions involves collecting primary data and using these observations to identify ions in solution using a procedure provided.
Carry out procedures to justify the identification of ions involves writing balanced equations for all the reactions where precipitates are formed.
Carry out procedures to comprehensively justify the identification of ions involves interpreting observations by recognising the formation of complex ions and writing balanced equations for these reactions.
4 Identification of ions must be supported by experimental observations and identification of all precipitates formed.
5 Ions to be identified will be limited to: Ag+, Al3+, Ba2+, Cu2+, Fe2+, Fe3+, Mg2+, Pb2+, Na+, Zn2+, Cl–, CO32–, I–, NO3–, OH–, SO42–. Na+ and NO3– are identified by a process of elimination.
6 Complex ions are limited to [FeSCN]2+ and those formed when OH–(aq) or NH3(aq) react with cations listed in EN 5 above, ie [Ag(NH3)2]+, [Al(OH)4]–, [Pb(OH)4]2–, [Zn(OH)4]2–, [Zn(NH3)4]2+, [Cu(NH3)4]2+.
7 Conditions of Assessment related to this achievement standard can be found at www.tki.org.nz/e/community/ncea/conditions-assessment.php.