The World of Metals and Non-metals

This set of flashcards covers the physical and chemical properties of metals and non-metals, focusing on malleability, ductility, conductivity, and their reactions with air and water as discussed in the Grade 7 Science curriculum.

The property that allows metals to be hammered into thin sheets is termed __________.

malleability

Materials like coal and sulfur, which shatter into pieces instead of flattening when struck, are described as __________.

brittle

The characteristic of metals that enables them to be stretched into long, thin wires is called __________.

ductility

Metals are described as __________ because they produce a ringing sound when struck.

sonorous

While most metals are very hard, __________ and __________ are unique because they are soft enough to be cut with a knife.

sodium and potassium

The metal __________ is notable for being in a liquid state at room temperature.

mercury

The process of iron developing brown deposits when exposed to both air and water is known as __________.

rusting

To prevent iron structures from deteriorating, a protective coating of __________ metal can be applied in a process called galvanisation.

zinc

When magnesium is burned in air, it forms an oxide that is __________ in nature, turning red litmus paper blue.

basic

Non-metals generally produce oxides that are __________ in nature.

acidic

To prevent a vigorous reaction with moisture and oxygen, the metal __________ is stored in kerosene.

sodium

The non-metal __________ is stored in water to prevent it from catching fire when exposed to the atmosphere.

phosphorus

Due to its extreme ductility, a single gram of gold can be drawn into a wire approximately __________ in length.

$$2\,km$$

The historic Iron Pillar in Delhi, which has resisted rusting for over $1600$ years, was built during the reign of __________.

Chandragupta II

Substances that allow heat and electricity to pass through them easily are classified as __________.

good conductors

There are currently __________ known elements, which act as the primary building blocks of matter.

$$118$$

The non-metal __________ is used in solution form as an antiseptic for wounds.

iodine

The non-metal element __________ is frequently used during the process of water purification.

chlorine

A mixture containing two or more metals, or a metal and a non-metal, is referred to as an __________.

alloy

Copper objects often develop a __________ coating when they undergo corrosion in the atmosphere.

green