Alloys differ from pure metals

The idea

The electrical conductivity and melting point of an alloy are lower than those of pure metals.

Wires and joins

Copper is used for electric circuits. A mixture of lead and tin is used to join electric wires.

How do alloys compare with pure metals?

• Lower conductivity and lower melting point
• Higher conductivity and higher melting point
• Exactly the same

Three examples

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Not the same as the pure metal

The electrical conductivity and melting point of an alloy are lower than those of the pure metals. Brass and bronze do not conduct well, so copper is used for circuits. Solder melts easily, so it can join electrical wires.

The electrical conductivity and melting point of an alloy are lower than those of pure metals.

Notes

An alloy's electrical conductivity and melting point are lower than those of pure metals.

Check yourself

Compared with pure metals, an alloy has ...

Why is copper, not brass, used for electrical circuits?

Solder is an alloy of ...

Solder is used for welding electrical wires together because it has ...

• higher electrical conductivity. The book says the electrical conductivity of an alloy is lower than that of pure metals.
• a higher melting point. The book says the melting point of an alloy is lower than that of pure metals.
• lower electrical conductivity and a lower melting point — correct. Yes!
• Brass, an alloy, is not a good conductor of electricity — correct. Yes!
• Brass is a gas. Brass is an alloy of copper and zinc, a solid.
• Brass contains no copper. Brass is an alloy of copper and zinc; it does contain copper.
• copper and zinc. Copper and zinc make brass.
• lead and tin — correct. Yes!
• copper and tin. Copper and tin make bronze.
• a high melting point. Solder has a low melting point.
• the best conductivity of all alloys. The book says solder is used because of its low melting point.
• a low melting point — correct. Yes!