Grades 9-12 Performance Task
Contributed by: New York State Education Department (NYSED)
Developed through University of Buffalo and NORC (1991)
Students will plan, design, and carry out an experiment
to determine an empirical formula for a hydrated salt X that will
tell students when all the water has been removed from hydrate crystals.
This task assesses students' abilities to develop
procedures for investigation, plans for recording and organizing
observations, collecting high quality observations and data, calculating
the coefficient of H20 in the empirical formula of hydrated salt
X, and making conclusions consistent with scientific principle and
the collected data.
This task is designed to take 80 minutes to complete
- 30 minutes for Part A (Experiment Design) and 50 minutes for Part
Overall Task Content Area:
- Physical Science
Specific Knowledge Areas:
- Chemical reactions
gathering, organizing, and representing data
formulating conclusions from investigational
applying scientific principles to develop explanations
and solve new problems
National Science Education Standards:
12 B PS 3: Chemical reactions: Grades 9-12
3.1 Chemical reactions occur all around us, for example in
health care, cooking, cosmetics, and automobiles. Complex chemical
reactions involving carbon-based molecules take place constantly
in every cell in our bodies.
12 A SI 1: Abilities necessary to do scientific
inquiry: Grades 9-12
1.2 Design and conduct scientific investigations. Designing
and conducting a scientific investigation requires introduction
to the major concepts in the area being investigated, proper equipment,
safety precautions, assistance with methodological problems, recommendations
for use of technologies, clarification of ideas that guide the inquiry,
and scientific knowledge obtained from sources other than the actual
investigation. The investigation may also require student clarification
of the question, method, controls, and variables; student organization
and display of data; student revision of methods and explanations;
and a public presentation of the results with a critical response
from peers. Regardless of the scientific investigation performed,
students must use evidence, apply logic, and construct an argument
for their proposed explanations.
1.3 Use technology and mathematics to improve
investigations and communications. A variety of technologies, such
as hand tools, measuring instruments, and calculators, should be
an integral component of scientific investigations. The use of computers
for the collection, analysis, and display of data is also a part
of this standard. Mathematics plays an essential role in all aspects
of an inquiry. For example, measurement is used for posing questions,
formulas are used for developing explanations, and charts and graphs
are used for communicating results.
1.4 Formulate and revise scientific explanations
and models using logic and evidence. Student inquiries should culminate
in formulating an explanation or model. Models should be physical,
conceptual, and mathematical. In the process of answering the questions,
the students should engage in discussions and arguments that result
in the revision of their explanations. These discussions should
be based on scientific knowledge, the use of logic, and evidence
from their investigation.
(Use the "hot" link on the PALS home
page to check the full text of related National Science Education
Standards, if desired.)
General Instructions to the Teacher:
This task is designed to take students approximately
80 minutes to complete.
Students will be working individually during this
Students should be ready to work as soon as the period
begins. The materials should be set out at each lab station, if
possible. A central supply area, if needed, should be easily accessible.
All supplies should be clearly labeled.
Materials for "Hydrated Salt":
- 1 crucible with cover
- 1 pair of crucible tongs
- 1 porcelain triangle
- 1 tripod
- bunsen burner with matches
- heat resistant tile
- hydrated sample X
- access to a periodic table
- safety goggles
- Safety goggles must be worn at all times
- Hot objects must be handled with tongs at all times.
- Should skin contact occur, flush thoroughly with water.
- Be careful.
- Teachers and students should always exercise appropriate safety
precautions and utilize appropriate laboratory safety procedures
and equipment when working on science performance tasks.