q('~What kind of paper is used to test for the acidic or alkaline properties of a liquid? ~litmus~It is a purple substance, obtained from plants.~Universal Indicator is another way of testing the acidity of a liquid.~');
q('~If a liquid turns Universal Indicator blue, what property must the liquid have?  ~alkaline~Some kinds of soap have this property.~And acids turn Universal Indicator red.~');
q('~What is the word for a liquid that is neither acidic nor alkaline? ~neutral~An example of a neutral liquid is water.~Neutral liquids turn Universal Indicator green/yellow.~');
q('~What is the name of the scale that is used to measure the acidity of liquids? ~pH~This scale ranges from 1 to 14.~Lemon juice is at the low end of the scale, whereas sodium hydroxide is at the top.~');
q('~Write the pH number for water.  ~7~Water tests in the middle of the pH scale.~This means that water is neither acidic nor alkaline.~');
q('~What is the color of the universal indicator solution containing a liquid with a pH of 1?  ~red~An example of this kind of liquid is sulphuric acid.~Liquids at the top end of the pH scale test dark blue.~');
q('~What is the color of the universal indicator solution containing water (pH7)?  ~yellow-green~Water is neutral.~Liquids that are more acidic than water test orange or red; those more alkaline test blue.~');
q('~What kind of ions are produced when acids are dissolved in water? ~hydrogen~Sulphuric acid is an example of a strong acid.~Acids can be neutralised by alkalis.~');
q('~What salts are produced when sulphuric acids are neutralised by an alkali? ~sulfates~Nitric acids produce nitrates.~And hydrochloric acids produce chlorides.~');
q('~Which gas is often produced when  metals react with acids? ~hydrogen~The gas that pops when lit with a burning splint.~Hydrogen is the most common gas on earth.~');
q('~Which compound (acid or alkali) often has a sour taste and usually reacts with metals? ~acid~Think of lemon juice.~The pH of acids is low.~');
q('~Which compound (acid or alkali or both) is soapy to touch? ~alkali~It is slippery like soap.~The pH of alkalis is high.~');
q('~What substance is missing from the following neutralisation reaction?<p> sulphuric acid + sodium hydroxide --->  water   +   ????? ~sodium sulfate~It is a kind of salt.~Sodium sulfate is used in matches and fertilisers.~');
q('~What substance is missing from the following neutralisation reaction?<p> ?????? + nitric acid  --->  magnesium nitrate + hydrogen ~magnesium~It is used in flares. It burns with a bright light.~Magnesium used in laboratorie often comes in silver ribbons.~');
q('~What is the name for the weather condition in which carbon dioxide and sulphur dioxide are dissolved in precipitation? ~acid rain~Precipitation is another word for rain!~Acid rain is responsible for the destruction of many elements of the ecosystem.~');
q('~What is the common name for the compound that is produced by the reaction of hydrochloric acid and sodium hydroxide? ~salt~You put it on your food to make the food taste better.~The chemical name for salt is sodium chloride.~');
q('~What is the name of the chemical that is produced by the reaction of sulphuric acid and magnesium? ~magnesium sulfate~It is often used as a medicine.~Magnesium sulfate is used in Epson salts for constipation.~');
q('~Nitric acid and ammonium hydroxide combine to produce ammonium nitrate. What is a common use of this compound? ~fertiliser~You put it in the soil to make plants grow better.~Ammonium nitrate is also used in explosives.~');
q('~Nitric acid and potassium hydroxide combine to produce potassium nitrate. What is a common use of this compound? ~explosives~This compound is used in bombs!~Potassium nitrate can also be used in fertilisers.~');
q('~What gas do you test for by lighting it with a burning splint? ~hydrogen~It makes a popping sound when lit.~Hydrogen ions are produced when acids are dissolved in water.~');
q('~What gas do you test for in lime water? ~carbon dioxide~The lime water goes milky in the presence of this gas. ~Carbon dioxide is the gas we breathe out.~');