2.3. Isotopes
A subsection of Chemistry, 0620, through 2. Atoms, elements and compounds
Listing 10 of 90 questions
The structures of some substances containing chlorine are shown. Cl − K+ Cl − K+ K+ Cl − K+ Cl − Cl − K+ Cl − K+ Cl Cl C A B D E C Cl Cl Cl Cl Cl Cl Cl Cl Cl Al Cl Cl Al Cl C H H F H F C C F Answer the following questions about these substances. Which substance is a diatomic molecule? Which substance represents part of an ionic structure? Which substance is an element? Explain your answer. Determine the simplest formula for substance D. 1 11 The symbols for two isotopes of chlorine are shown. Cl Cl How do these two isotopes differ in their atomic structure? Determine the number of neutrons present in one atom of the isotope Cl . Draw the electronic structure of a chlorine atom. Show all shells and all electrons. [ 1 11
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THEORY
2016
Paper 3, Variant 1
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The structures of some substances containing carbon are shown. C C H H H H Ca2+ C2 2– C2 2– C2 2– C2 2– C2 2– C2 2– Ca2+ Ca2+ Ca2+ Ca2+ Ca2+ C C C C C C C C C C C C C CC C C C C C C C C C C C C C C C C C C C C CC C C C C C C C C C C C C C C C C C C C C C C C C C C C C C C C C C C C C C C C C C C C C C C C C C C C C C A B D E C C C C C H H H H H Cl Cl Cl Cl Cl C Answer the following questions about these substances. Which two substances have giant covalent structures? and Which substance decolourises aqueous bromine? Which substance is most likely to be a gas at room temperature and pressure? Which substance is a hydrocarbon? Determine the simplest formula for substance D. 1 10 Two isotopes of carbon are C and C. How do these two isotopes differ in their atomic structure? Determine the number of neutrons present in one atom of the isotope C. [ 1 10
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THEORY
2016
Paper 3, Variant 3
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The symbols of the elements in Period2 of the Periodic Table are shown. Li Be B C N O F Ne Use the symbols of the elements in Period 2 to answer the questions that follow. Each symbol may be used once, more than once or not at all. Give the symbol of the element that: makes up approximately 78% of clean, dry air ������������������������������������������������������������� contains atoms with only three electrons in the outer shell ������������������������������������������ contains atoms with only nine protons �������������������������������������������������������������������������� exists as graphite ���������������������������������������������������������������������������������������������������������� is an alkali metal ����������������������������������������������������������������������������������������������������������� only has an oxidation number of zero. ������������������������������������������������������������������������� Boron, B, has two isotopes. State the meaning of the term isotopes. Table2.1 shows the relative masses and the percentage abundances of the two isotopes of boron. Table 2.1 relative mass of isotope percentage abundance of isotope Calculate the relative atomic mass of boron to one decimal place.  relative atomic mass = 
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THEORY
2023
Paper 4, Variant 1
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Sulfur is a Group VI element. A sample of sulfur contains two isotopes, 32S and 34S. Complete Table 5.1 to show the number of protons and neutrons in one atom of each isotope of sulfur. Table 5.1 32S 34S protons neutrons State why these isotopes have identical chemical properties. State the mass of 6.02 × 1023 atoms of 34S. Include units in your answer. State the name of the amount of substance which contains 6.02 × 1023 atoms. Table 5.2 shows the relative abundance of these isotopes of sulfur in the sample. Table 5.2 atom 32S 34S relative abundance 95% 5% Calculate the relative atomic mass of sulfur in this sample to one decimal place. relative atomic mass = Sulfur reacts with magnesium to form magnesium sulfide, MgS, an ionic compound. Complete the dot-and-cross diagram in of the ions in magnesium sulfide. Give the charges on the ions. Mg S State why MgS has a high melting point. State why molten MgS conducts electricity. An acid containing sulfur reacts with sodium hydroxide, NaOH, to form a salt and water. The salt has the formula Na2SO3. Deduce the formula of this acid. Deduce the formula of the anion in Na2SO3. Na2SO3 is oxidised by acidified aqueous potassium manganate(. State what VII refers to in the name potassium manganate(. State the colour change when this reaction happens. from to . ,  ,
0620_s24_qp_42
THEORY
2024
Paper 4, Variant 2
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Questions Discovered
90