Chemistry - General

Question 1

Define element

Answer 1

Substance that cannot be broken down into anything simpler by chemical means. Contains only one type of atom (e.g oxygen, sulfur, sodium)

Question 2

Define compound

Answer 2

Substance formed by chemical combination of two or more elements (e.g water, carbon dioxide, methane)

Question 3

Define solid

Answer 3

A substance keeps it’s own shape. Atoms/molecules vibrate close together, in a fixed, regular arrangement

Question 4

Define liquid

Answer 4

Substance fills bottom of container. Particles are closely attracted but free to move, no regular arrangement

Question 5

Define gas

Answer 5

Particles fill all available space. Particles move randomly at high speed with large spaces between them

Question 6

Melting point

Answer 6

Temperature at which solid changes to liquid (and reverse)

Question 7

Boiling point

Answer 7

Temperature at which liquid changes to gas (and reverse)

Question 8

The smallest particle of an element that can take part in a chemical reaction

Answer 8

Atom (e.g iron atom, carbon atom, oxygen atom)

Question 9

Smallest part of an element or compound that can exist alone

Answer 9

Molecule (oxygen molecule, carbon dioxide molecule)

Question 10

Atom or group of atoms with a positive or negative charge

Answer 10

Ion (e.g Na+, O2-, CO32-

Question 11

Define ionic bond

Answer 11

Bond formed between two ions where the attractive force is between the positive and negative charges.

Question 12

Define covalent bond

Answer 12

Bond formed between to atoms where the electrons in the outer energy shell are shared between the atoms.