A. choose the correct option. 1. which of these is composed of one kind of atoms only? a. element b. compound c. mixture d. all of these 2. which of the following is a property of metals? a they are generally solids at room temperature c. they have high melting and boiling points b. d. they normally have high densities all of the above 3. graphite is: a. a metal b. an alloy c. a form of carbon d. a form of iron

( A ) element is composed of one kind of atoms only .

( B ) Properties of metals are - they are generally solids at room temperature , they have high melting and boiling points ,  they normally have high densities ,

Correct option is - All of the above.

( C ) Graphite is a - ( c ) form of carbon .

Explanation:

Element -

Element is composed of all same type of atoms or element is a substance with all same number of protons .

Element is the smallest or the simplest substance and cannot be broken down using any chemical reaction .

Metal -

Elements are classified into metals and non metals .

Properties of metals are -

1. State - Metals are generally solid at room temperature , except Mercury , with liquid state at room temperature .

2. Boiling point and melting point - Metals have a very high boiling and melting point , with Tungsten having the highest melting point .

3. Density - Metals have high density and are quite heavy , Iridium and osmium have the highest densities .

Graphite -  

Graphite is one of the allotropic form of carbon .