Making our resources

What is corrosion?

The destruction of a material through reactions with substances in the environment.

What physical barriers can be used to protect against corrosion?

Grease, paint, or a thin layer of metal can be used as physical barriers to protect against corrosion.

What is sacrificial protection?

Sacrificial protection involves adding a more reactive metal to the surface of a material to prevent corrosion.

How is rust formed?

Rust is formed through the reaction between iron, water, and oxygen.

What are two alloys of copper?

Brass (copper and zinc) and bronze (copper and tin) are two alloys of copper.

What are gold alloys in jewellery made from?

Gold alloys in jewellery are made from gold mixed with copper, zinc, and silver.

What are steel alloys made from?

Steel alloys are made from iron, carbon, and other metals.

What is a property of aluminium alloys?

Aluminium alloys generally have low densities.

What is the main difference between soda-lime and borosilicate glass?

Borosilicate glass has a much higher melting point compared to soda-lime glass.

Give two examples of clay ceramics.

Pottery and bricks are two examples of clay ceramics.

What two things do the properties of polymers depend on?

The properties of polymers depend on their monomers and the conditions under which they are formed.

What is the main difference between thermosetting and thermosoftening polymers?

Thermosetting polymers do not soften when heated, while thermosoftening polymers do.

What is a composite?

A composite is a mixture of a matrix and reinforcements.

Name two composites.

Plywood and reinforced concrete are two examples of composites.

What is the balanced symbol equation for the Haber process?

N2(g) + 2H2(g) = 2NH3(g) is the balanced symbol equation for the Haber process.

What is ammonia used for?

Ammonia is used for making fertilizers.

What is the effect of increasing the temperature of the Haber process on the yield, rate, and cost?

Increasing the temperature decreases yield, increases rate, and increases cost.

What is the effect of increasing the pressure of the Haber process on the yield, rate, and cost?

Increasing the pressure increases yield, increases rate, and increases cost.

What catalyst do we use for the Haber process?

Iron is the catalyst used for the Haber process.

What are the conditions for the Haber process?

The conditions for the Haber process are 450 °C, 200 atm pressure, and the use of an iron catalyst.

What is an NPK fertiliser?

An NPK fertiliser is a formulation containing soluble compounds of nitrogen, phosphorus, and potassium.