How do you convert a substance’s mass in grams to an amount in moles using its relative formula mass?
Divide the mass in grams by the substance’s relative formula mass.
AQA GCSE Combined Science: Trilogy (8464) — Chemistry — Higher · 5.3.2.3
Revise AQA GCSE Combined Science: Trilogy (8464) — Chemistry — Higher specification point 5.3.2.3, Using moles to balance equations (HT only), with free active-recall flashcards. Flip through the set or review every question and answer below.
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How do you convert a substance’s mass in grams to an amount in moles using its relative formula mass?
Divide the mass in grams by the substance’s relative formula mass.
How are mole amounts used to balance a symbol equation?
Simplify the mole amounts to the smallest whole-number ratio and use that ratio as the balancing coefficients.
Why can mole amounts be used to determine the stoichiometric ratio in a balanced equation?
Mole amounts are directly proportional to the numbers of particles reacting or forming.
What does it mean to change the subject of an equation?
Isolate a chosen quantity on one side, expressing it in terms of the other quantities.
Why must the same valid operation be applied to both sides when rearranging an equation?
To preserve equality, so the rearranged equation expresses the same relationship.
In what order are operations generally undone when rearranging an equation?
In reverse order, using inverse operations, such as subtraction for addition and division for multiplication.
When the chosen quantity is in a denominator, what can be done first to rearrange the equation?
Multiply to remove the denominator, then undo the remaining operations.