72:["$","div",null,{"className":"SmxAaG_md","lang":"$undefined","children":[["$","p","p-0",{"children":"Test for hydrogen gas?"}]]}] 73:["$","div",null,{"className":"SmxAaG_md","lang":"$undefined","children":[["$","p","p-0",{"children":["Brought near a flame, it burns with a ",["$","strong","strong-0",{"children":"pop"}]," sound."]}]]}] 74:["$","div",null,{"className":"SmxAaG_md","lang":"$undefined","children":[["$","p","p-0",{"children":"Test for carbon dioxide?"}]]}] 75:["$","div",null,{"className":"SmxAaG_md","lang":"$undefined","children":[["$","p","p-0",{"children":["It turns ",["$","strong","strong-0",{"children":"lime water milky"}]," (calcium carbonate forms)."]}]]}] 76:["$","div",null,{"className":"SmxAaG_md","lang":"$undefined","children":[["$","p","p-0",{"children":"Why does lime water turn clear again when excess carbon dioxide is passed?"}]]}] ab:T6f3,

\ce{CaCO3}

ac:Tc5d,

\ce{Ca(HCO3)2}

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\ce{2NaOH + Zn -> Na2ZnO2 + H2}

79:["$","div",null,{"className":"SmxAaG_md","lang":"$undefined","children":[["$","p","p-0",{"children":[["$","span","code-0",{"className":"SmxAaG_mathInline SmxAaG_mathInlineScroll","data-math":"inline","tabIndex":0,"dangerouslySetInnerHTML":{"__html":"$ad"}}]," (sodium zincate + hydrogen)."]}]]}] 7a:["$","div",null,{"className":"SmxAaG_md","lang":"$undefined","children":[["$","p","p-0",{"children":"What is neutralisation?"}]]}] 7b:["$","div",null,{"className":"SmxAaG_md","lang":"$undefined","children":[["$","p","p-0",{"children":["The reaction of an ",["$","strong","strong-0",{"children":"acid"}]," with a ",["$","strong","strong-1",{"children":"base"}]," to form a ",["$","strong","strong-2",{"children":"salt and water"}],"."]}]]}] 7c:["$","div",null,{"className":"SmxAaG_md","lang":"$undefined","children":[["$","p","p-0",{"children":"Are metal oxides acidic or basic? Non-metal oxides?"}]]}] 7d:["$","div",null,{"className":"SmxAaG_md","lang":"$undefined","children":[["$","p","p-0",{"children":["Metal oxides are ",["$","strong","strong-0",{"children":"basic"}],"; non-metal oxides are ",["$","strong","strong-1",{"children":"acidic"}],"."]}]]}] 7e:["$","div",null,{"className":"SmxAaG_md","lang":"$undefined","children":[["$","p","p-0",{"children":"Why does an acid solution conduct electricity but a glucose solution does not?"}]]}] ae:T4bf,

\ce{H+}

7f:["$","div",null,{"className":"SmxAaG_md","lang":"$undefined","children":[["$","p","p-0",{"children":["Acids give ",["$","strong","strong-0",{"children":"ions"}]," (",["$","span","code-0",{"className":"SmxAaG_mathInline","data-math":"inline","tabIndex":"$undefined","dangerouslySetInnerHTML":{"__html":"$ae"}}],") in water; glucose does not ionise."]}]]}] 80:["$","div",null,{"className":"SmxAaG_md","lang":"$undefined","children":[["$","p","p-0",{"children":"What is a hydronium ion?"}]]}] af:T9ad,

\ce{H3O+}

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Concentrated: a lot of acid per unit volume."}]]}] 8c:["$","div",null,{"className":"SmxAaG_md","lang":"$undefined","children":[["$","p","p-0",{"children":"What colour does universal indicator show at pH 7?"}]]}] 8d:["$","div",null,{"className":"SmxAaG_md","lang":"$undefined","children":[["$","p","p-0",{"children":"Green (neutral)."}]]}] 8e:["$","div",null,{"className":"SmxAaG_md","lang":"$undefined","children":[["$","p","p-0",{"children":"pH range in which the human body works?"}]]}] 8f:["$","div",null,{"className":"SmxAaG_md","lang":"$undefined","children":[["$","p","p-0",{"children":["About ",["$","strong","strong-0",{"children":"7.0 to 7.8"}],"."]}]]}] 90:["$","div",null,{"className":"SmxAaG_md","lang":"$undefined","children":[["$","p","p-0",{"children":"Below which pH does tooth decay start?"}]]}] 91:["$","div",null,{"className":"SmxAaG_md","lang":"$undefined","children":[["$","p","p-0",{"children":["Below ",["$","strong","strong-0",{"children":"pH 5.5"}],"."]}]]}] 92:["$","div",null,{"className":"SmxAaG_md","lang":"$undefined","children":[["$","p","p-0",{"children":"Why is milk of magnesia used for acidity?"}]]}] 93:["$","div",null,{"className":"SmxAaG_md","lang":"$undefined","children":[["$","p","p-0",{"children":["It is a ",["$","strong","strong-0",{"children":"mild base"}]," (magnesium hydroxide) that neutralises excess stomach acid."]}]]}] 94:["$","div",null,{"className":"SmxAaG_md","lang":"$undefined","children":[["$","p","p-0",{"children":"Remedy for a red ant bite, and why?"}]]}] 95:["$","div",null,{"className":"SmxAaG_md","lang":"$undefined","children":[["$","p","p-0",{"children":["Apply a mild base such as ",["$","strong","strong-0",{"children":"baking soda"}],"; it neutralises the methanoic acid."]}]]}] 96:["$","div",null,{"className":"SmxAaG_md","lang":"$undefined","children":[["$","p","p-0",{"children":"Rain is called acid rain below which pH?"}]]}] 97:["$","div",null,{"className":"SmxAaG_md","lang":"$undefined","children":[["$","p","p-0",{"children":["Below ",["$","strong","strong-0",{"children":"5.6"}],"."]}]]}] 98:["$","div",null,{"className":"SmxAaG_md","lang":"$undefined","children":[["$","p","p-0",{"children":"Predict the pH of a salt from a strong acid and a weak base."}]]}] 99:["$","div",null,{"className":"SmxAaG_md","lang":"$undefined","children":[["$","p","p-0",{"children":[["$","strong","strong-0",{"children":"Acidic"}]," (pH below 7), e.g. ammonium chloride."]}]]}] 9a:["$","div",null,{"className":"SmxAaG_md","lang":"$undefined","children":[["$","p","p-0",{"children":"Why is sodium carbonate solution basic?"}]]}] 9b:["$","div",null,{"className":"SmxAaG_md","lang":"$undefined","children":[["$","p","p-0",{"children":["It is a salt of a ",["$","strong","strong-0",{"children":"weak acid"}]," (carbonic) and a ",["$","strong","strong-1",{"children":"strong base"}]," (sodium hydroxide)."]}]]}] 9c:["$","div",null,{"className":"SmxAaG_md","lang":"$undefined","children":[["$","p","p-0",{"children":"What is water of crystallisation?"}]]}] b0:Td77,

\ce{CuSO4.5H2O}

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\ce{NaHCO3}

b2:T1257,

\ce{Na2CO3.10H2O}

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