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Level 1 Science
90944 (1.5): Demonstrate understanding of aspects of acids and bases
Credits: FourYou should answer ALL parts of ALL questions in this booklet.A table of ions and a periodic table are provided in the resource booklet for Science 90944 (1.5). Check that you have been supplied with the resource booklet for Science 90944 (1.5).If you need more space for any answer, use the page(s) provided at the back of this booklet and clearly number the question.Check that this booklet has pages 2-11 in the correct order and that none of these pages is blank.YOU MUST HAND THIS BOOKLET TO YOUR TEACHER AT THE END OF THE ALLOTTED TIME.
For Assessor's use only
Achievement with Merit
Achievement with Excellence
Demonstrate understanding of aspects of acids and bases.
Demonstrate in-depth understanding of aspects of acids and bases.
Demonstrate comprehensive understanding of aspects of acids and bases.
Overall Level of Performance
You are advised to spend 60 minutes answering the questions in this booklet.QUESTION ONE: IONIC COMPOUNDSMagnesium and calcium atoms both form ions with a charge of +2. Magnesium atoms form Mg2+ ions, and calcium atoms form Ca2+ ions.Explain why magnesium and calcium atoms form ions with the same charge of +2. In your answer, you should:define an ionexplain why atoms form ionsidentify the group on the periodic table where the two atoms are foundexplain why both magnesium and calcium ions have a charge of +2.Sodium and beryllium atoms form ions with different charges.Complete the table below.
Periodic table group number
Electron arrangement of atom
Charge on the ion that the atom forms
Explain why the ions in sodium hydroxide combine to give the formula NaOH but the ions in beryllium hydroxide combine to give the formula Be(OH)2.In your answer, you should:compare the charges on the individual ions found in the compounds sodium hydroxide and beryllium hydroxideexplain why the ions combine in the ratios the way they do to form the compounds NaOH and Be(OH)2.QUESTION TWO: ISOTOPES and ionsLithium atoms can exist in different forms called isotopes. Two of these isotopes are Lithium-6 (Li) and Lithium-7 (Li).Explain whyLi andLi are both neutral atoms. In your answer, you should fully describe their atomic structure and state their electron configuration.Berylium can exist as an isotope in the form of beryllium-7 (Be).Discuss how the mass ofBe compares withLi ANDLi. In your answer, you should:consider the atomic structure of each atomconsider the meaning of the numbers '6' and '7' in terms of the atomic structuresexplain how the particles within an atom contribute to its overall mass.You may draw labelled diagrams in the box below to support your answer....