Chemistry Unit 2

By the end of this unit teachers and students will be able to:

• access a set of suitable photographic images for a titration experiment, either by using provided images or by making their own set using a mobile phone or digital camera (Activity 1)
• download Photo Story 3 from this website or the internet; use the application to make a pictorial sequence of images to describe and support the practical techniques involved in volumetric analysis; use scientific text and narration to support these images (Activity 2)
• add value to the photo story by further adding transitions, music and additional text to explain the processing of the results; understand how digital images can be used to develop a student-centred approach to volumetric analysis to support active science learning (Activity 3)
• make the edited Photo Story 3 available on Google Videos for viewing and sharing with colleagues/students for feedback: explore how it can support formative assessment (Activity 4).

Investigative work using volumetric analysis offers an opportunity for teachers and students to engage in chemical experimental work and gain mathematical competence. However, obstacles that could deter student-centred learning include:

• lack of sufficient glassware to support individual practical work
• lack of experienced technical support
• the complexity of the chemistry needed in this topic area
• the challenge of teaching mathematical concepts
• the topic of the mole and associated calculations is seen by students and teachers as too abstract.

The use of e-technology in the form of Photo Story 3 offers the opportunity to motivate students and help them develop their understanding of a difficult topic. The ease of use of this software can act as a motivational tool to encourage students not only to be active, but also to work collaboratively with their peers.

In addition to using Photo Story, this topic can be linked to a scenario that gives a reason for the work. The practical could be put into a context, for example an environmental investigation of acid rain or an analyst's work on quality control of foods.

These are some solutions to the potential barriers to effective teaching and learning in this area:

• Lack of sufficient equipment for individual class use
  This approach will allow students to interact and discuss the skills needed to perform titrations.
• Lack of experienced technical support
  A lesson could be prepared by using the basic apparatus and the Photo Story 'titration'. All this entails is provision of the basic equipment and computer access. Students will then use the technology as a learning tool. It is hoped that they will support each other to create an interesting and individual presentation. The complexity of the presentation will depend on the level of interest and ability of the students.
• Difficult calculations and subject knowledge, which makes the teaching of this topic didactic
  Difficult calculations and subject knowledge is addressed by the introduction of a basic formula, which students can use to process results. The Photo Story presentation could allow the introduction of more complex work if the students are sufficiently motivated.
• Students not motivated by an abstract topic
  The interest stimulated by the technology will motivate students and consequently aid their learning of a difficult topic.

These are the software and hardware requirements:

• digital camera or mobile phone and appropriate leads
• a microphone attached to a PC
• audio speakers attached to computer
• Windows Photo Story 3 (free download)
• Windows Media Player
• volumetric analysis equipment.

• Gathering and Saving Your Images (Activity 1)
• Using Photostory (Activity 2)
• Advanced Features (Activity 3)
• Uploading Video to Google (Activity 4)

You will need to log into the Triple Science Learning Community to view or download these resources. The links below will direct you to another page of the website. Select 'download this resource' and you will be prompted for your password for the learning community.

• To see an example of a complete Photo Story on carrying out a titration click Carrying out a titration; can you do better?. It is envisaged that this will be used as a guide for teachers to support students' work.
• There is also available a set of photographic images for student use. Click on bank of images.
• For staff and students there is also a set of instructions on carrying out a titration, with guidance on completing calculations. Click on Instructions to carry out a titration.

• For teachers who are not confident in using volumetric exercises in analysis, the prepared Photo Story resource could be shown prior to student involvement. It can then be used to support the experimental work or as an idea for students to then carry out their own preparation of a Photo Story – by completing activities 1–4. Students could review the prepared Photo Story and make improved ones themselves.
• It could be shown to the technician to involve them in understanding what the students are doing.
• Worksheets on the calculations and so on can be adapted so that students could produce their own voice over to explain the steps involved in the calculations.

Websites

• Method for preparing a titration reagent
• Titration
• Pearson lab bench activity
• Biodiesel Tutorial
• YouTube - Titration demonstration

 Additional reading material

• You may find information on volumetric analysis in an applied GCSE text book or, if you have a sixth form, an AS Chemistry text book should have information on titrations.