quantative chemistry Flashcards
(14 cards)
What does the law of conservation of mass state?
Mass of reactants = mass of products
What is relative formula mass (Mr)?
The sum of the relative atomic masses of the elements shown in the formula.
How do you calculate the percentage of an element?
Percentage of element = (total relative mass of element ÷ relative formula mass of compound) x 100
How do you calculate the mass of an element (using percentage?)
Mass of an element = Total mass of a compound x percentage (decimal)
How does mass change occur in experiments?
Gases escaping (less mass) or forming solids (more mass)
How do you calculate uncertainty?
Range/2
What is the volume of 1 mole of a gas at room temp/pressure?
24dm^3
What is a mole?
The mass of one mole of a substance is grams is equal to its relative formula mass
How many atoms are in a mole/what is Avogadro’s constant?
6.02 x 102^3
How do you calculate the moles in a given mass?
Mass/Mr x Mol
stupid godforsaken silly formula die
How do you calculate percentage yield?
%yield = (mass of product actually made ÷ maximum theoretical yield) x 100
What is atom economy?
The atom economy is a measure of the amount of starting materials that ended up as useful products.
Why is a high atom economy desirable?
Environmental and economic reasons.
