Topic 3: Quantitative Chemistry ✅ Flashcards
What is the Law of Conservation of Mass equation?
The total mass of reactants equal the total mass of products
How do you calculate the relative formula mass of a compound?
By adding the relative atomic masses of the elements that make the compound and then multiply it by the number of atoms of that element in the compound, then add the numbers together.
What is the law of conservation of mass?
A law that states that no atoms can be created or destroyed in a chemical reaction.
What is relative atomic mass?
The average mass of the atom.
What is another name for the relative formula mass of a compound?
Relative molecular mass
How does burning of wood change the mass of products?
It decreases it as carbon dioxide and water (and other gases) is released.
Give 3 example of how the mass of the product can change?
Burning wood
Corrosion if metals
Zinc+Hydrochloric acid
Every chemical measurement involves some…
… uncertainty
How can you reduce uncertainty?
By repeating the measurement from experiments several times and calculating an average from them.
Why must chemical equations be balanced?
To make sure that there are the same number or atoms of an element before and after a reaction.
What does the molecular formula show?
The actual amount of atoms which make up a molecule.
Name an example of a molecular formula.
Glucose C6H12O6
What does Empirical formula show?
The simplest ratio of atoms which make up a molecule.
Name and example of empirical formula.
Glucose CH2O
What are moles?
A measurement if chemical amounts.
One mole is a substance is ____ atoms of that substance.
6.02 X 10 to the power of 23
What is the number 6.02 X 10 to the power of 23 known as in terms of moles?
Avogadros Constant