unit 1 exam

write the electronic configuration for the following elements

Na(11) , He(2) , Cl(17)

The mass of a piece of iron is 78 gm , putted inside a cylinder with reading 10 cm3

so the density of the iron equals ......... gm/cm3

• 10

• 7.8

• 78

• 0.12

The smallest part of matter which can exist freely is ....

• compound

• molecule

• element

• atom

A substance has high melting point ......

• rubber

• ice

• iron

• wax

An alloy used in making jewels ........

• copper-gold alloy

• nickel-chrome alloy

• iron-steel alloy

• silver-copper alloy

The only liquid metal

• Hydrogen

• Helium

• Mercury

• Bromine

A process where the solid matter changes into liquid matter is .......

• Freezing

• Melting

• Vaporization

• condensation

Give reason for

The separation of crude petroleum oil by heating ?

Evaluate responses using AI:

OFF

Give reason for

Equal volume of different substances has different masses ?

Evaluate responses using AI:

OFF

Ammonia molecule formed of 2 hydrogen atoms and 1 oxygen atom

• true

• false