science chemistry

• What is the name of the process when an acid and an alkali react?

  "neutralisation
• Soluble salts can be made by mixing acids and alkalis. What name is given to this type of reaction?


  neutralisation
• A concentrated solution has fewer or more acid particles per litre than a dilute solution.

  more
• Universal indicator turns blue in alkaline solutions around pH 10.
• Blue litmus paper is bleached white by chlorine
• Which salt would form if you reacted hydrochloric acid with calcium hydroxide?

  The metal in a salt comes from the base (calcium).Hydrochloric acid produces chloride salts.So, the salt produced is calcium chloride.
• Besides the salt, name the other product that is formed when an acid reacts with an alkali. Give the name, not the formula.

  acid + alkali → salt + waterWater is always produced during a reaction between an acid and an alkali.Disagree with your mark?Next question
• What name is given to substances (both soluble and insoluble) such as metal hydroxides and metal oxides that can neutralise acids?

  base
• When an acid reacts with a base a salt is produced along with another product. Name this product.


  acid + base → salt + waterWater is always produced during a reaction between an acid and a base.
• What salt is produced when copper oxide reacts with hydrochloric acid?

  Copper oxide produces copper salts. Hydrochloric acid produces chloride salts. These react together to form copper chloride.
• What is the name given to reactions where reduction and oxidation occur?

  redox reactions
• Metals can be arranged in order of their reactivity in a list called a reactivity __________. What one word completes this sentence?

  series
• Certain __________ metals like gold are found as pure metals rather than ores in the earth.

  Unreactive metals have not reacted with other elements to form compounds.
• Most metals are found chemically joined to other elements in substances known as... what?

  compound
• Iron is often found joined to another element. What is this element?

  the iron has reacted with the oxygen in the atmosphere to form iron oxide.
• What element is commonly used to reduce iron oxide?

  Carbon is more reactive than iron and it is very abundant and inexpensive. It reduces the iron oxide by removing the oxygen.
• Is carbon more or less reactive than iron?

  more reactive
• What process is usually used to extract metals that are more reactive than carbon?

  Metals that are more reactive than carbon cannot be extracted by heating with carbon, so electrolysis is used instead.
• What type of energy source does electrolysis use?

  electrical energy
• Some metals are extracted using electrolysis. In order for this to work the metal ore must be in a __________ form.

  molten, Metal ores must be molten so that the metal ions can move to the negative electrode.
• What metal is commonly recycled from drinks cans?

  Most drinks cans are made of aluminium.
• Photosynthesis is controlled by three environmental factors; namely, light intensity, carbon dioxide availability and temperature.

  Disagree with your mark?

  Next question
• A limiting factor is the name given to any factor which, when in short supply, affects the rate of reaction.
• If the light is moved nearer to the plant, the volume of gas collected in the tube will increase. Photosynthesis is affected by light intensity.
• Plants grow best in environments that have high levels of carbon dioxide and are warm and light. Greenhouse B has these conditions.
• There is a relationship between photosynthesis and light levels. The further away the source of light from the pondweed, the smaller the volume of oxygen produced.
• Group 1 metals react with non-metals to form ionic compounds.
• Transition metals have much higher melting points than alkali metals.
• Alkali metals have such a low density that they can float on water.
• Alkali metals are much more reactive than transition metals.
• Group 1 elements are called the alkali metals.
• Alkali metals react violently with non-metals.
• Alkali metals are soft and can easily be cut with a knife.
• Most alkali metals have a melting point below 100°C.
• The elements in group 0 are very unreactive. They are known as the noble gases.