C1- Atomic Structure Flashcards
What is an atom?
An atom is the smallest part of any substance. All substances are made up of atoms.
What are the masses and charges of the subatomic particles?
Protons (found in nucleus)-
Charge= +1
Relative Mass= 1
Electrons (found in shells)-
Charge= -1
Relative Mass= 0
Neutrons (found in nucleus)-
Charge= 0
Relative Mass= 1
Why does an atom have no overall charge?
They have the same number of positively charged protons and negatively charged electrons.
What does the mass number of an atom tell you?
The number of protons and neutrons in the nucleus.
What does the atomic number of an atom tell you?
The number of protons.
What is an isotope?
The same element with the same number of protons but different number of neutrons.
Describe the plum pudding model.
Mainly empty space with a tiny nucleus where the mass is concentrated. The positive charge is in the nucleus and electrons orbit the nucleus.
What was the order of discovery of the subatomic particles?
Electron,
Proton,
Neutron.
What did Mendeleev do that was different to other scientists?
Mendeleev left gaps and he was flexible with this arrangement and switched order of elements. He still arrange them in order of atomic mass.
What is an element?
An element is a substance of only one type of atom.
Elements can be classified into two groups based on their properties; what are these groups?
Metals and Non-metals.
What is a compound?
Compounds are two or more types of elements chemically bonded.
They can only be separated into elements by chemical reactions.
How are the elements in the modern periodic table arranged?
Atomic number.
What does the group number and period tell us about elements?
Group number- Number of electrons in the outer shell.
Periods- Number of electron shells.
Explain what happens to the reactivity of metals as you go down group 1?
The reactivity increases.
There is more shielding because the outer most negative electron is further away from the positive nucleus resulting in weaker attractive force.
