A+CHRISTMAS+MIX+UP

One of Santa’s little helpers has been mischievous. Mrs Claus made up a biscuit mix containing flour, baking soda and icing sugar. When her back was turned a naughty elf added bowls of mixtures that look like Mrs Claus’s but might contain talcum powder, Epsom salts, Lo salt (potassium chloride) or flour.
 * __ A Christmas mix up __**

Your task is to help Mrs Claus identify which mixture is hers so she can get on with making her biscuits.



You have 5 mixtures labelled A to E. You need to carry out some scientific tests to determine what each of the bowls contains. The possible ingredients in each of the mixtures are Epsom salts (magnesium sulphate) Talcum powder (magnesium silicate) Flour Baking soda Sugar Lo salt (potassium chloride)

You will need to work as a team to figure out what is in each bowl. Your team should contain up to 4 people but be careful who you chose to work with, you have only a short time to solve the problem and sloppy workers will affect your results.


 * To win the challenge your team needs - **

¨ Every member of your team to have a completed results table ¨ To have cleared everything away neatly and wiped your table ¨ To have worked safely, worn safety goggles at all times

**__ Tests to carry out – (wear safety goggle at all times) __**

** Test for Lo salt ** Equipment needed – test tube, test tube rack, wire loop, Bunsen burner, heat mat. Take a little bit of the powder place it in a test tube, dissolve it in about 1 cm3 of water. Dip in your wire loop and place in the blue flame of your Bunsen burner. Note the colour. A pinky/purple colour shows potassium is present. An orange colour shows sodium is present (sodium is in baking powder). The orange colour of sodium can often mask other flame colours.

** Test for flour ** Equipment needed – test tube, test tube rack, iodine solution. Take a spatula of the powder and place it in a test tube. Add iodine solution to the powder. Note the colour. The iodine will turn blue-black if starch is present.

** Test for baking soda ** Equipment needed - test tube, test tube rack, vinegar (or any acid). Take a spatula of the powder and place it in a test tube. Add vinegar to the powder. Note what happens. The powder will fizz if sodium bicarbonate is present.

** Test for sugar (Glucose) ** Equipment needed – Test tube, test tube rack, Benedict’s solution, water bath (or beaker of hot water). Take a spatula of the powder and place it in a test tube. Dissolve it in 1 cm3 of water. Add 4 drops of Benedict’s solution and place the tube in the water bath (or hot water in a beaker).

** Results ** Record your results in the table given to you. Highlight the tests that gave positive results. Mrs Claus’s mixture contains flour, baking powder and icing sugar. Use your results to work out which mixture is hers. Remember to clear everything away neatly before presenting your results to your teacher.  **A** ||    ||  ||  ||  ||  **B**  ||  ||  ||  ||  ||  **C**  || <span style="display: block; mso-element-anchor-horizontal: margin; mso-element-frame-hspace: 9.0pt; mso-element-top: 18.55pt; mso-element-wrap: around; mso-element: frame; mso-height-rule: exactly; text-align: center;"> || <span style="display: block; mso-element-anchor-horizontal: margin; mso-element-frame-hspace: 9.0pt; mso-element-top: 18.55pt; mso-element-wrap: around; mso-element: frame; mso-height-rule: exactly; text-align: center;"> || <span style="display: block; mso-element-anchor-horizontal: margin; mso-element-frame-hspace: 9.0pt; mso-element-top: 18.55pt; mso-element-wrap: around; mso-element: frame; mso-height-rule: exactly; text-align: center;"> || <span style="display: block; mso-element-anchor-horizontal: margin; mso-element-frame-hspace: 9.0pt; mso-element-top: 18.55pt; mso-element-wrap: around; mso-element: frame; mso-height-rule: exactly; text-align: center;"> || <span style="display: block; mso-element-anchor-horizontal: margin; mso-element-frame-hspace: 9.0pt; mso-element-top: 18.55pt; mso-element-wrap: around; mso-element: frame; mso-height-rule: exactly; text-align: center;"> **D** <span style="display: block; mso-element-anchor-horizontal: margin; mso-element-frame-hspace: 9.0pt; mso-element-top: 18.55pt; mso-element-wrap: around; mso-element: frame; mso-height-rule: exactly; text-align: center;"> || <span style="display: block; mso-element-anchor-horizontal: margin; mso-element-frame-hspace: 9.0pt; mso-element-top: 18.55pt; mso-element-wrap: around; mso-element: frame; mso-height-rule: exactly; text-align: center;"> || <span style="display: block; mso-element-anchor-horizontal: margin; mso-element-frame-hspace: 9.0pt; mso-element-top: 18.55pt; mso-element-wrap: around; mso-element: frame; mso-height-rule: exactly; text-align: center;"> || <span style="display: block; mso-element-anchor-horizontal: margin; mso-element-frame-hspace: 9.0pt; mso-element-top: 18.55pt; mso-element-wrap: around; mso-element: frame; mso-height-rule: exactly; text-align: center;"> || <span style="display: block; mso-element-anchor-horizontal: margin; mso-element-frame-hspace: 9.0pt; mso-element-top: 18.55pt; mso-element-wrap: around; mso-element: frame; mso-height-rule: exactly; text-align: center;"> || <span style="display: block; mso-element-anchor-horizontal: margin; mso-element-frame-hspace: 9.0pt; mso-element-top: 18.55pt; mso-element-wrap: around; mso-element: frame; mso-height-rule: exactly; text-align: center;"> **E** <span style="display: block; mso-element-anchor-horizontal: margin; mso-element-frame-hspace: 9.0pt; mso-element-top: 18.55pt; mso-element-wrap: around; mso-element: frame; mso-height-rule: exactly; text-align: center;"> || <span style="display: block; mso-element-anchor-horizontal: margin; mso-element-frame-hspace: 9.0pt; mso-element-top: 18.55pt; mso-element-wrap: around; mso-element: frame; mso-height-rule: exactly; text-align: center;"> || <span style="display: block; mso-element-anchor-horizontal: margin; mso-element-frame-hspace: 9.0pt; mso-element-top: 18.55pt; mso-element-wrap: around; mso-element: frame; mso-height-rule: exactly; text-align: center;"> || <span style="display: block; mso-element-anchor-horizontal: margin; mso-element-frame-hspace: 9.0pt; mso-element-top: 18.55pt; mso-element-wrap: around; mso-element: frame; mso-height-rule: exactly; text-align: center;"> || <span style="display: block; mso-element-anchor-horizontal: margin; mso-element-frame-hspace: 9.0pt; mso-element-top: 18.55pt; mso-element-wrap: around; mso-element: frame; mso-height-rule: exactly; text-align: center;"> ||
 * <span style="display: block; mso-element-anchor-horizontal: margin; mso-element-frame-hspace: 9.0pt; mso-element-top: 18.55pt; mso-element-wrap: around; mso-element: frame; mso-height-rule: exactly; text-align: center;"> |||||||| <span style="display: block; mso-element-anchor-horizontal: margin; mso-element-frame-hspace: 9.0pt; mso-element-top: 18.55pt; mso-element-wrap: around; mso-element: frame; mso-height-rule: exactly; text-align: center;"> Chemical tests ||
 * <span style="display: block; mso-element-anchor-horizontal: margin; mso-element-frame-hspace: 9.0pt; mso-element-top: 18.55pt; mso-element-wrap: around; mso-element: frame; mso-height-rule: exactly; text-align: center;"> || <span style="display: block; mso-element-anchor-horizontal: margin; mso-element-frame-hspace: 9.0pt; mso-element-top: 18.55pt; mso-element-wrap: around; mso-element: frame; mso-height-rule: exactly; text-align: center;"> Lo-Salt || <span style="display: block; mso-element-anchor-horizontal: margin; mso-element-frame-hspace: 9.0pt; mso-element-top: 18.55pt; mso-element-wrap: around; mso-element: frame; mso-height-rule: exactly; text-align: center;"> Flour  || <span style="display: block; mso-element-anchor-horizontal: margin; mso-element-frame-hspace: 9.0pt; mso-element-top: 18.55pt; mso-element-wrap: around; mso-element: frame; mso-height-rule: exactly; text-align: center;"> Baking soda  || <span style="display: block; mso-element-anchor-horizontal: margin; mso-element-frame-hspace: 9.0pt; mso-element-top: 18.55pt; mso-element-wrap: around; mso-element: frame; mso-height-rule: exactly; text-align: center;"> Sugar  ||
 * <span style="display: block; mso-element-anchor-horizontal: margin; mso-element-frame-hspace: 9.0pt; mso-element-top: 18.55pt; mso-element-wrap: around; mso-element: frame; mso-height-rule: exactly; text-align: center;">
 * <span style="display: block; mso-element-anchor-horizontal: margin; mso-element-frame-hspace: 9.0pt; mso-element-top: 18.55pt; mso-element-wrap: around; mso-element: frame; mso-height-rule: exactly; text-align: center;">
 * <span style="display: block; mso-element-anchor-horizontal: margin; mso-element-frame-hspace: 9.0pt; mso-element-top: 18.55pt; mso-element-wrap: around; mso-element: frame; mso-height-rule: exactly; text-align: center;">
 * <span style="display: block; mso-element-anchor-horizontal: margin; mso-element-frame-hspace: 9.0pt; mso-element-top: 18.55pt; mso-element-wrap: around; mso-element: frame; mso-height-rule: exactly; text-align: center;">
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Mrs Claus’s biscuit mix is