Curriculum Studies – Stage 1 or 2 Chemistry Teaching Unit: Solution Stoichiometry

Context/ Rationale

This Inquiry Unit has been developed for a South Australian Certificate of Education (SACE) Stage 1 (year 11) Chemistry class at Keith Area School (KAS) in rural South Australia. There are six students, five females and one male. Students are in a combined class with three year twelve students, two females and one male. This unit is planned for four weeks with four lessons per week (16 lessons total). Students will complete homework to support their learning and complete unfinished work and assignments. The summative assessment tasks for this unit of work will be a test. Students will undertake various formative assessments such as quizzes, worksheets, short assignments and exit cards. This unit covers an adaptation of the beginning of Topic 4: Mixtures and Solutions in the Science Understanding (SU) stream of SACE Stage 1 Chemistry. The learning program aligns with specially selected parts of Subtopic 4.1: Miscibility and Solutions, 4.2: Solutions of Ionic Substances and 4.3: Quantities in Reactions with additional relevant concepts and skills added through the Science Inquiry Skills (SIS) and Science as a Human Endeavour (SHE) streams of SACE Chemistry. The relevant learning outcomes, i.e. what students will know, understand and be able to do as a result of this unit, are shown below.

KUDs What the students will know, understand, and be able to do because of the learning program implemented. Understanding of the requirements of the specialist area curriculum statement Understand:

• Students will understand many reactions that are important to humans occur in solution, including reactions in the cells of living organisms, the soil, the air, and the oceans.

• Students will understand that substances dissolve differently in other substances depending on properties.

• Students will understand that chemical changes can be represented by chemical equations.

Know:

• Students will know that chemical equations can be written to describe a chemical change.

• Students will know that the concentration of a solution can be described in terms of

mass concentration (mass of solute per unit volume, ) or as molar concentration (moles of solute per unit volume, c).

• Students will know that dissociation of ionic compounds is the process in which the ionic substance separates into cations and anions.

• Students will know that chemicals react in definite proportions.

• Students will know that many ionic substances are soluble in water. This is particularly so for Na+, K+ and NH4

+.

• Students will know that equations can be written to represent the dissociation and hydration of ions that occurs when ionic substances dissolve in water.

• Students will know that some ionic substances are not very soluble in water; such substances form as precipitates when solutions containing the relevant ions are mixed.

• Students will know that water can be described as hard water or soft water.

• Students will know that ions cause hardness in water and can be removed from the solution to reduce the hardness.

• Students will know that “electric current” is the flow of electric charge, i.e. the flow of free moving charged particles such as ions.

• Students will know that Coulomb’s law stating that like charges repel and opposite charges attract, with a force proportional to the product of the charges.

Do:

• Students will be able to distinguish between the terms, solute, solvent and solution.

• Students will be able to write chemical equations when given the reactant and products of a reaction.

• Students will be able to define the term concentration and appreciate that it is measured in moles per litre regardless of the volume given.

• Students will be able to undertake calculations using the relationship and its

rearrangements.

• Students will be able to undertake calculations using the relationship and its rearrangements.

• Students will be able to undertake conversions between mass concentrations and molar concentrations.

• Students will be able to undertake stoichiometric calculations for precipitation reactions.

• Students will be able to describe the formation of ion-dipole interactions when ionic substances dissolve in water.

• Students will be able to write equations for the dissolving of ionic substances in water.

• Students will be able to distinguish between precipitation and dissociation reactions.

• Students will be able to write ionic equations for precipitation reactions.

• Students will be able to distinguish between hard water and soft water.

• Students will be able to explain why soap forms a scum in water containing calcium ions.

• Students will be able to use Coulomb’s law to explain attraction between particles.

• Students will be able to account for the changes in conductivity observed upon melting an ionic compound or dissolving it in water.

• Students will be able to use the solubility table.

Skills and Capabilities

What skills and capabilities they will develop and be able to apply in different contexts including the enduring understandings? Students will be engaging with the SACE General Capabilities throughout this unit in both general class work and assessment items. The ways that the Literacy, Numeracy and ICT capabilities are present in this unit are described in detail below. There are many opportunities for the other general capabilities to be developed throughout the course of this unit of work, that of which are not as prominent as the three described. These will be more heavily incorporated in other units of work throughout the year. Students will engage with the Literacy capability through reading, notetaking, vocabulary work and written tasks. Students will learn the appropriate text types for different tasks as well as how to represent information in a chemical context. Symbols, equations and language will be highly focused in this section as students delve deeper into chemical equations and stoichiometry. This unit has a high numeracy focus with all stoichiometric calculations involving numerical values. Students will be able to see how mathematical processes are involved in real contexts in Chemistry. Students will use mathematical skills and operations to calculate quantities and concentrations of solution. Key parts of the numeracy capability accessed in this unit of work are “solving problems using calculation and critical thinking skills” and “calculating and predicting values by manipulating data, using appropriate scientific conventions” (SACE Board of South Australia, 2018). The Information and Communication Technology (ICT) capability will be present in a small way throughout this unit. Students will access videos and animations on the internet to consolidate their learning. They will also use ICT for research and collating information, such as on the Class Glossary (bit.do/chemglossary). Students will also use calculator technologies for mathematical calculations. Students will consider how ICT has allowed chemists to find information and apply chemical knowledge to new contexts.

Differentiation/ Flexibility

What flexibility exists within the evaluations to support all students in a fair and consistent manner? Demonstrated awareness of diverse learning needs reflected in pedagogical approaches, learning experiences and resources. Despite the small size of the year 11 chemistry class, there is still a variety of diverse needs amongst students. Due to this, a variety of pedagogical approaches will be used to not only vary the way content is delivered but to provide alternative resources and learning experiences for students. Some of these pedagogical approaches include practical tasks, collaborative work, explicit teaching, questioning, use of electronic media, film, video, animation and more. It is essential for teachers to differentiate their learning programs to accommodate the needs of each student in the class. Extra support materials will be available for students who require assistance in certain areas of the course. Scaffolded worksheets are implemented for extra support when required.

Assessment Overview and/or Evidence of Understanding

Appropriateness of the evaluations of student learning to address the learning outcomes as specified in the Inquiry unit How you will know whether the students have achieved the desired understanding, what evidence will be suitable to demonstrate this? The assessment tasks for this unit of work will be constructed to provide evidence of student understanding. The summative assessment task for this unit of work is a Skills and Assessment task in the form of a test. Many formative assessment techniques will be used during the unit. These include the more formal types of assessment such as exit cards, quizzes, self and peer assessments, worksheets and homework tasks as well as the informal questioning, thumbs-up/down responses etc. Each of these will be outlined as appropriate below.

Statement about Model of

Inquiry

In this unit of work, the models of inquiry that will be engaged with most prominently are Structured Inquiry and Guided Inquiry. Students will be engaging with a variety of questions throughout the unit, many of which promote higher order thinking skill development. Students will engage in many inquiry concepts through practical applications of science in the classroom. Students will also have many opportunities to develop their SIS, especially the one stated below: “Scientific information can be presented using different types of symbols and representations. • Select, use, and interpret appropriate representations, including: mathematical relationships, such as ratios diagrams writing equations

to explain concepts, solve problems, and make predictions” (SACE Board of South Australia, 2018). This part of the curriculum will be particularly apparent during the calculations part of stoichiometry. Students will also engage in inquiry-based laboratory tasks for Precipitation Reactions, Conductivity of Solutions (resource 16) and Hard and Soft Water (resource 18). During these laboratory sessions, students will be given a problem or question to solve using their laboratory skills and scientific method. There are also support materials for students in these laboratory sessions, to help promote development of the inquiry and laboratory skills. See the individual resources for further information.

Inquiry Unit Plan

Lesson Number

Topic/Theme Specific Content/ Key Ideas Learning Outcomes/Activities Resource (Number)

Assessment task and opportunities for feedback

1 Pre-Assessment

Pre-Assessment - Vocabulary - Solutions - Mole Calculations - Dissociation

Students will undertake a preassessment quiz to diagnose understandings at the current time. Homework: Watch http://bit.do/stoichiometry1 and answer the questions on the worksheet.

1 2

Pre-assessment quiz - Feedback given to

students - Learning program

adjusted accordingly.

2 Vocabulary

Distinguish between the terms, solute, solvent and solution. Define the term concentration and appreciate the units it is measured in. Concentration of a solution

- Measured in moles per litre or grams per litre.

Class Glossary – Google Doc http://bit.do/chemglossary Vocabulary Lift Flaps Organiser Concentration Sheet Exit Card

3 4 5 6

Exit Card

3-6 Stoichiometric Calculations

Calculate the concentration given the number of moles (or mass) of solute and volume of solution. Use the relationships

and

Explicit Teaching PowerPoints Videos Worksheets Textbook Questions (Stage 1 Essentials Workbook) Task Cards Google Forms Quizzes (Exit Activities) Explore changes in the concentration using simulation: https://phet.colorado.edu/sims/html/concentration/latest/concentration_en.html

7, 9 8 9

Google Forms Quizzes Worksheets Exit Cards

7 Creating Solutions

Making Solutions of Known Concentration

Lab skills: Making solutions Video/Worksheet Worksheet

10

Exit Card

8 Dilution Dilutions Dilution Information Sheet 11

Chemistry Dilutions Questions Supporting Website: https://www.wikihow.com/Do-Serial-Dilutions

10 Worksheet Questions

9-10 Dissociation Revise the concepts of dissociation.

• Students will know that many ionic substances are soluble in water. This is particularly so for Na+, K+ and NH4

+.

• Students will know that equations can be written to represent the dissociation and hydration of ions that occurs when ionic substances dissolve in water.

• Students will be able to describe the formation of ion-dipole interactions when ionic substances dissolve in water.

• Students will be able to write equations for the dissolving of ionic substances in water.

Solubility Table

Explicit Teaching – Review of Dissociation Watch: http://bit.do/dissociation1 Dissociation Poster: A3 Poster Task of different ionic compounds dissociating in water. Students will use solubility table from Stage 1 Essentials Workbook.

12

Dissociation Poster - Formative

assignment - Returned to Students

with grade and comment

11-12 Precipitation Distinguish between precipitation and dissociation reactions. Students will be able to write ionic equations for precipitation reactions. Solubility Table

Introduction to Precipitation Reactions – Homework Task: Watch video at http://bit.do/precipitationreactions and complete assigned questions on worksheet. Lab Session – Inquiry into Precipitation Precipitation Worksheet Precipitation Exit Card

13 14 15

Exit Card

13-14 Conductivity in Solution

Define what is meant by an "electric current".

• Students will know that “electric current” is the flow of electric charge, i.e. the flow of free moving charged particles such as ions.

Explicit Teaching – PowerPoint Use of videos for group discussion: https://www.youtube.com/watch?v=4FLFy3mrjD4 https://www.youtube.com/watch?v=4WillWjxRWw

Exit Card

Account for the changes in conductivity observed upon melting an ionic compound or dissolving it in water.

• Students will be able to use Coulomb’s law to explain attraction between particles.

• Students will be able to account for the changes in conductivity observed upon melting an ionic compound or dissolving it in water

• Students will know that Coulomb’s law stating that like charges repel and opposite charges attract, with a force proportional to the product of the charges.

Explain why conductivity depends on the concentration of ions in solution. Account for the non-conductivity of most pure discrete molecular compounds and most giant molecular substances.

Laboratory Task: Conductivity of Solutions 16

Laboratory Report - Formative assessment. - Returned to students

with feedback.

15-16

Hard and Soft Water

Investigate the difference between hard water and soft water. Determine the ions which cause hardness and explore various ways of removing these ions from solution.

• Students will be able to distinguish between hard water and soft water.

• Students will be able to explain why soap forms a scum in water containing calcium ions.

See, Think, Wonder (Knowledge, n.d.) Laboratory Task (Pearson Education, 2000-2004). Compare and Contrast Worksheet (House of the Three Dinosaurs, n.d.). Explicit Teaching Support Websites: http://www.bbc.co.uk/schools/gcsebitesize/science/triple_aqa/water/hard_soft_water/revision/1/

17 18 19

Laboratory Task - Formative Assessment - Returned to students

with feedback.

Exit Card

Various other exit tickets will be used at appropriate stages of the unit plan. These are included as resource 20. Please Note: The resource folio is a comprehensive list but not total list of the resources that will be used in this unit.

Resource Folio Resource 1 - Mixtures and Solutions Pre-Assessment (Right) This task will be used in lesson 1 of Term 2 as a pre-assessment for the unit. It has been created to provide a refreshment of the topics covered previously this year as well as to pre-assess knowledge of the next topic. The questions have been designed to address different levels of student readiness. Different types of questions have been asked with different formatted answers to provide opportunity for students to present their ideas in different ways. Students have also been asked questions about personal circumstances. This is to speed up the process of getting to know students as well as to end the quiz in an easy to answer style.

Resource 2 – Crash Course Chemistry Stoichiometry Video (Left) Students will watch a video for homework on stoichiometry. This should be mostly revision of content learned last term. It will act as a refresher tool and as consolidation.

Resource 3 – Year 11 Chemistry Glossary Hyperlink: bit.do/chemglossary I have established a Google Document for students to collaborate in creating a glossary of terms that are used this term. This glossary can be accessed by all students and will be added to on a continual basis. Not only is this an online collaborative space but is somewhere for students to share their knowledge and support each other. This will be used throughout the unit with reminders to students to create new additions when new or unfamiliar terms arise.

Resource 4 – Vocabulary Task This resource was created by The Science Penguin on Teachers Pay Teachers (The Science Penguin, 2014). I will use it to go through definitions of each word before beginning with the main body of the lesson (Resource 4). Students will cut along the dotted lines and glue the long, left hand side into their books. They will then write the definitions underneath each flap. This will work alongside the collaborative glossary that I have established (Resource 2).

Resource 5 – Concentration Information Sheet (right) This resource was created to clearly outline the concept of concentration of solution. Students will be guided through this sheet, highlighting relevant parts. Students will then use this sheet as a reference point when they engage with inquiry questions throughout the unit of work.

Resource 6 – Exit Card (below)

Students will complete this exit card at the end of the lesson about concentration of

solution. Students will know that dilute solutions have lower amounts of solute than

concentrated solutions and their illustrations should reflect this.

Students will engage with the problemsolving strategies that have been previously

taught in class, i.e. regarding how to answer explain questions.

Resource 7 – Molarity Calculations (Erikson, 2018) (left)

This resource will be used just after the concept of concentration is introduced. It

has simple questions that gradually get more challenging and therefore will allow

students to ease into the calculations.

Resource 8 – Stoichiometry Task Cards (below)

As students progress through this part of the broader unit, they will need to review

the content. These task cards provide an excellent way to do so, with questions

about previous learning of stoichiometry (with mass) included.

Resource 9 – Google Forms Quizzes

Google Forms will be used to create quizzes such as those below. These quizzes will be run at different stages throughout the unit as a homework task or as an

exit card for the lesson.

Resource 10 – Stage 2 Chemistry – Stoichiometry (Stone, 2012)

This resource, created by Anthony Stone at the Australian Science and Mathematics School, will have its title edited for the Stage 1 class. Many questions will be

used with appropriate challenge alterations made. Students will complete pages 1 and 2 to practice their calculation skills for concentration stoichiometry. Page 3

will be used for homework after the 8th lesson of the unit. During the 8th lesson students will learn about dilutions through explicit teaching and then will practice

calcuations for homework.

Resource 11 – Dilutions Information Sheet (Blake, 2018a) (Left)

This sheet was created by Ken Blake, science and maths teacher at

Keith Area School in South Australia. This sheet will be handed out to

students during the dilutions section of this unit plan. Students will use it

as a information reference and as an example of dilution calculations.

Resource 12 – Dissociation Poster Task Sheet (Right)

Students will create a poster of an ionic compound dissociating in water. It will have a brief

description of the ionic compound and its uses before showing the dissociation of the ions in

water. Students will have 1 lesson and homework time to complete the poster. It will be

formatively assessed.

Resource 13 – Precipitation Reactions – Crash Course Chemistry (below)

Students will watch the video about Precipitation Reactions at

bit.do/precipitationreactions from Crash Course Chemistry. The questions below will

be completed for homework. This will provide students with an engaging

introduction to precipitation reactions before explicit teaching and lab work.

Resource 14 – Precipitation Worksheet (Blake, 2018b) (above).

This resource will be used during the precipitation part of the unit plan

after students are exposed to explicit teaching and a laboratory session

on precipitation reactions. Students will complete these calculations using

the skills and knowledge they would have developed in the stoichiometry

section.

Resource 15 – Precipitation Freyer Diagram (directly below)

This Freyer Diagram will be used as an exit card to formatively assess

students’ understanding of precipitation. In this format, a Freyer Diagram,

students are asked the definition, characteristics, examples of and illustration

of the concept in the middle.

Resource 16 – Solution Conductivity Laboratory Task(The Regents of

the University of California, 2017) (directly below)

This resource will be adapted for the Stage 1 class. Students will be given a

question and therefore need to find a solution to this question using the

scientific method. Students will be testing if it is better to sit in an ocean, lake

or bath tub of jelly during a lightning storm. The inquiry objective section is

highlighted in yellow below. Students will use their knoweldge of

conductivity, substance classification and chemical and physical properties.

Link:

https://www.mrl.ucsb.edu/sites/default/files/mrl_docs/ret_attachments/

curriculum/solution%20conductivity%20lesson%20plan.pdf

Resource 17 – See, Think, Wonder (Knowledge, n.d.)

Students will undertake this activity as a warm-up in the first lesson about hard and soft water. They will be shown the image of the shower head and asked to

complete the See, Think, Wonder task. This will help make connections between chemistry and real life.

Resource 18 – Laboratory of Hard or Soft Water (Pearson Education, 2000-2004).

This laboratory task will be completed after students do the ‘See, Think, Wonder’ task in

resource 15. Students will be given the inquiry based problem and some materials to

solve it. Students then need to devise a plan to work out which of the water samples is

hard or soft water. Students will be given opportunity to develop their inquiry skills and

understanding of scientific method through this task. Scaffolded questioning may be

requried to support students who need help in deveoping inquiry skills.

Resource 19 – Compare/Contrast The Differences Between Hard Water and Soft Water (House of the

Three Dinosaurs, n.d.).

Students will compelte this task as a homework activity after the last lesson of the unit. This will follow from

explicit teaching about hard and soft water, the ions involved and how to remove these ions.

Resource 20 – Exit Tickets (below)

These exit tickets have been created as generic resources for any type of lesson. They will be used as

appropriate during this unit plan. Students will have the opportunity to fill them in during the last 5-10 minutes

of the lesson.

References

Blake, K. (2018a). Dilutions. Keith, South Australia: Keith Area School.

Blake, K. (2018b). Precipitation Keith, South Australia: Keith Area School.

Erikson, P. (2018). Molarity Calculations. In Commonwealth of Pennsylvania (Ed.).

House of the Three Dinosaurs. (n.d.). Compare/Contrast: Hard Water & Soft Water: Teachers Pay Teachers.

Knowledge, U. (n.d.). See, Think, Wonder Organizer FREE: Teachers Pay Teachers.

Pearson Education. (2000-2004). Hard or Soft Water: TeacherVision.

SACE Board of South Australia. (2018). Stage 1 Chemistry Subject Outline (for teaching 2018).

https://www.sace.sa.edu.au/documents/652891/3814095/Stage+1+Chemistry+Subject+Outline+%28for+teaching+in+2018%29.docx/ab01a4de-7202-

31c6-2b7a-b0f25946fc5f.

Stone, A. (2012). Stage 2 Chemistry - Stoichiometry: Australian Maths and Science School (ASMS).

The Regents of the University of California. (2017). Solution Conductivity. In Materials Research Laboratory at UCSB: AN NSF MRSEC (Ed.), Lesson Plan,

Student Version, Teacher Version and Supplemental Materials. Santa Barbara: Materials Research Laboratory.

The Science Penguin. (2014). Science Vocabulary Lesson: Teachers Pay Teachers.