Science test

Question 1

What is the difference between atoms and compounds

Answer 1

Atoms are the smallest particle to exist that makes up everything. A compound is made up of 2 or more different chemical elements combined in a fixed ratio.

Question 2

What is the difference between elements and compounds

Answer 2

An element is a pure substance only made up of one atom. and a compound is made up of different atoms.

Question 3

What is the atomic number

Answer 3

The number shown at the top corner of each element On the periodic table, to symbolise how many protons in the nucleus.

Question 4

Define combustion and corrosion

Answer 4

corrosion is the combination of oxeygen water and metal to create a metal compund called rust.
Combustion is a chemical reaction resulting in the release of energy, light or heat, like a sparkler.

Question 5

How to identify if a change is chemical or physical

Answer 5

A physical change can be reversed back to what it was. A chemical change cannot be reversed and will be forever in that state (burning wood)

Question 6

compare location and properties of metallic and non-metallic elements
from the Periodic Table

Answer 6

The majority of elements are metals and they are found on the left and in the middle of the periodic table. Most metals share a lot of properties, such as being good conductors of heat and electricity. Non-metals often have the opposite properties. For example, they are usually poor conductors of heat and electricity.

Question 7

what is the difference between a molecule and a mixture.

Answer 7

a molecule is a group of two or more atoms combined by a chemical bond. A mixture is made up of multiple chemical substances that are not chemically bonded