You are in browse mode. You must login to use MEMORY

level: Level 1 of Chemistry

Questions and Answers List

Question	Answer
What is an element?	An element is a substance of only one type of atom
Which elements are more likely to form negative ions?	Non-Metals
Which elements are more likely to form positive ions?	Metals
What two subatomic particles make up the mass of an atom?	Protons and neutrons
What does the atomic number represent?	The number of protons in the nucleus
Why are atoms electrically neutral?	They have the same number of electrons and protons
Describe the structure of an atom	A nucleus made up of protons and neutrons with electros orbiting around at a distance
What is formed when a non-metal reacts with a non-metal?	Covalently bonded molecule
What is formed when a metal reacts with a non-metal?	An ionic compound A salt
What are ions?	Ions are charged particles, they are formed when atoms lose or gain electrons.
Give the electronic configurations of the following to demonstrate how shells are occupied by electrons He(2), Be(4),F(9),Na(11) and Ca(20)	He 2 Be 2,2 F 2,7 Na 2,8,1 Ca 2,8,8,2
What is an isotope?	Atoms of the same element that have a different number of neutrons
How do you calculate the number of neutrons in an elements?	Subtract the atomic number from the mass number
What is a mixture?	A mixture consists of two or more elements or compounds NOT chemically combined
What is a compound?	Two or more elements combined chemically
Elements can be classified into two groups based on their properties; what are these groups?	Metal and non-metals