Grade 9-12 Performance Task
Developed by: New York State Education Department (NYSED)
University of Buffalo and NORC (1991, revised 1993)

Description:

Students will determine the concentration of an unknown solution.

This task assesses students' abilities to state a hypothesis, develop procedures for investigation, plan for recording and organizing observations and data, observe, collect data, create a graph, calculate a number of moles to neutralize an unknown solution, and write a conclusion consistent with the collected data.

This task is designed to take students approximately 80 minutes to complete - 30 minutes for Part A and 50 minutes for Part B.

Overall Task Content Area:

Physical Science

Specific Knowledge Areas:

Properties and changes of properties in matter

Performance Expectations:

• conducting investigations
• using equipment
• gathering, organizing, and representing data
• formulating conclusions from investigational data
• applying scientific principles to develop explanations

National Science Eduation Standards:

8 B PS 1: Properties and changes of properties in matter: Grades 5-8
1.2 Substances react chemically in characteristic ways with other substances to form new substances (compounds) with different characteristic properties. In chemical reactions, the total mass is conserved. Substances often are placed in categories or groups if they react in similar ways; metals is an example of such a group.

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.)

National Council of Teachers of Mathematics:

NO1: Understand numbers, ways of representing numbers, relationships among numbers, and number systems:
Grades 9-12 u. develop a deeper understanding of very large and very small numbers and of various representations of them

NO3: Compute fluently and make reasonable estimates:
Grades 9-12 o. judge the reasonableness of numerical computations and their results

AL2: Represent and analyze mathematical situations and structures using algebraic symbols:
Grades 9-12 k. write equivalent forms of equations, inequalities, and systems of equations and solve them with fluency-mentally or with paper and pencil in simple cases and using technology in all cases

AL3: Use mathematical models to represent and understand quantitative relationships:
Grades 9-12 f. draw reasonable conclusions about a situation being modeled

DAP1: Formulate questions that can be addressed with data and collect, organize, and display relevant data to answer them:
Grades 9-12 l. understand the meaning of measurement data and categorical data, of univariate and bivariate data, and of the term variable

PS1: Build new mathematical knowledge through problem solving:
Grades 9-12

RP3: Develop and evaluate mathematical arguments and proofs:
Grades 9-12

COM4: Use the language of mathematics to express mathematical ideas precisely:
Grades 9-12

General Instructions to the Teacher:

This task is designed to take approximately 80 minutes to complete - 30 minutes for Part A and 50 minutes for Part B.

Students will be working individually during this exercise.

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 "Acid-Base Titration":

At each station students should have: