Metals and Non-Metals Science - Metals and Non-Metals

An important ore of zinc metal is:

The noble gas having only two electrons in its valence shell is:

Which property of copper and aluminium makes them suitable:
For making electric wires?

What iron compound is present in haematite ore? Also write its chemical formula.

Give reason for the following:
Silver, gold and platinum are used to make jewellery.

What is the name of the chemical bond formed:
By the sharing of electrons between two atoms?

Show the formation of NaCl from sodium and chlorine atoms by the transfer of electron(s).

Draw the electron-dot structure of a hydrogen chloride molecule:

1. Which inert gas does the H atom in HCl resemble in electron arrangement?
2. Which inert gas does the Cl atom in HCl resemble in electron arrangement?

The atomic number of an element X is 12.

1. What must an atom of X do to attain the nearest inert gas electron configuration?
2. Which inert gas is nearest to X?

Explain how, mercury is extracted from its sulphide ore (cinnabar). Give equations of the reactions involved.

What is meant by 22 carat gold? Name the metals which are usually alloyed with gold to make it harder.

What happens when calcium reacts with chlorine? Write an equation for the reaction which takes place.

What is a thermite reaction? Explain with the help of an equation. State one use of this reaction.

How are the properties of an alloy different from those of the constitutent elements?

Using electron-dot diagrams which show only the outermost shell electrons, show how a molecule of nitrogen, N, is formed from two nitrogen atoms. What name is given to this type of bonding? (Atomic number of nitrogen is 7)

A black metal oxide XO is used as a catalyst in the preparation of oxygen gas from potassium chlorate. The oxide XO is also used in ordinary dry cells. The metal oxide XO cannot be reduced satisfactorily with carbon to form metal X.

1. Name the metal X.
2. Name the metal oxide XO.
3. Which reducing agent can be used to reduce XO to obtain metal X?
4. Name another metal which can also be extracted by the reduction of its oxide with the above reducing agent.

State and explain the reaction, if any, of the following metals with a solution of copper sulphate:

1. Gold.
2. Copper.
3. Zinc.
4. Mercury.

You are given samples of three metals — sodium, magnesium and copper. Suggest any two activities to arrange them in order of their decreasing reactivities.

State whether the following statement is true or false:
The aqueous solution of an ionic compound conducts electricity because there are plenty of free electrons in the solution.

State whether the following statement is true or false :
Non-metals react with dilute acids to produce a gas which burns with a ‘pop’ sound.

Fill in the following blanks with suitable words:
The non-metal present in steel is _______.

Fill in the following blanks with suitable words:
Ordinary aluminium strips are not attacked by water because of the presence of a layer of _________ on the surface of aluminium.

Fill in the following blanks with suitable words:
The alloy in which one of the metals is mercury is called an _______.

Fill in the following blanks with suitable words:
Magnesium liberates ________ gas on reacting with hot boiling water.

Fill in the blanks in the following sentence:
Two atoms of the same element combine to form a molecule. The bond between them is known as _________ bond.