Module 1 - Atoms and Reactions. Flashcards
What is an Isotope?
Isotopes are atoms of the same element with different number of neutrons.
What is the Mass (Nucleon) Number?
Mass (Nucleon) Number is the number of particles (protons and neutrons) in the nucleus.
Carbon exists as three main isotopes what are they?
Carbon Exists as a mixture of the isotopes carbon-12 carbon-13 and carbon-14.
Why is the mass number of each isotope of carbon different?
The Mass Number is different because each isotope has a different number of neutrons.
Why do different isotopes act in the same way?
Different isotopes all act in the same way this is because chemical reactions involve electrons so therefore neutrons make no difference to the reactivity.
What is the international standard for the measurement of relative mass?
The international standard for the measurement of relative mass is Carbon-12.
What are Atomic masses measured using?
Atomic masses are measured using a unit called the unified atomic mass unit.
What is the mass of an atom of Carbon-12?
12u. Thus, the mass of one twelfth of an atom of Carbon-12 is 1u.
How would you found out the relative isotopic mass of an isotope?
For an Isotope the relative isotopic mass is the same as the mass number.
Define Relative Atomic Mass.
Relative Atomic Mass is the weighted mean mass of an atom of an element compared with one twelfth of an atom of carbon-12.
How can you work out the Relative Molecular Mass?
You can find out the relative molecular mass by adding together the relative atomic masses of each atom making up the molecules.
Define Relative molecular mass.
Relative molecular mass is the weighted mean mass of a molecule compared with one twelfth of carbon-12 atoms.
How is the amount of substance measured?
The amount of substance is measured using the mole. (abbreviation mol.)
What is Avogadro’s Constant?
The Avogadro constant is the number of atoms per mole of carbon-12 isotope.
(6.02x10^23)
How can you find one mole of atoms of an element?
You can find out one mole of atoms of any element as it is it’s relative atomic mass in grams.
