Physical and Chemical Change
Is melting ice a physical or chemical change?
Physical
Which element is the first on the Periodic Table?
Hydrogen
Proton, Neutron and Electron
What is an element?
A substance made of only one type of atom
Who came up with the word 'atom'?
The word atom comes from the Greek word 'atomos' meaning indivisble.
Name a sign that a chemical change has occurred.
Gas produced / colour change / temperature change / new substance formed
What are the rows of the Periodic Table called?
Periods
What charge is a proton?
Positive
What is a molecule?
Two or more atoms chemically bonded together
What is the name of the model we now use for the atom?
Atomic/Nuclear model.
Is rusting a chemical or physical change?
Chemical
What are the columns of the Periodic Table called?
Groups
Where are electrons found?
In the electron shell around the nucleus
What is a compound?
Two or more different elements chemically bonded
What was Thomsons delicious model called?
Plum pudding model
Is making salt water a physical or chemical change?
Physical, it has just become a mixture and can be reversed.
Where do we find metals on the periodic table?
Left and centre
What does the atomic number tell us about an atom?
The number of protons
Is O2 a molecule or a compound?
Molecule, because its not 2 or more different elements.
Which experiment discovered the nucleus?
Rutherford shooting particles at a sheet of gold.
Cooking an egg is what type of change and why?
Chemical change — new substances form and it cannot be reversed easily
What did Mendeleev do specially with his Periodic Table?
Left gaps in his Periodic Table that predicted new elements.
If an atom has 12 protons and its atomic mass is 25, how many neutrons does it have?
13
What is the difference between a mixture and a compound?
Mixtures are not chemically bonded and can be separated physically; compounds are chemically bonded.
What did Neils Bohr add to the atomic model?
Electron shells/waves