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Combined Science: Chemistry

GCSE · Edexcel · foundation

QuestionsFlashcards

Obtaining & Using Metals
Reversible Reactions & Equilibria
- Reversible Reactions & Equilibrium
  3
- The Haber Process
  4

Group 1
- Group 1 (Alkali Metals)
  4
- Group 1: Reactivity & Electronic Configurations
  4
Group 7
Group 0

Reacting Masses Flashcards

All 4 cards in this deck

How is the mass of a product related to the mass of a reactant in a balanced equation?: mass of product = mass of reactant × (total relative formula mass of the product ÷ total relative formula mass of the reactant), using the balancing numbers from the equation
In a reacting mass calculation, what do you multiply a relative formula mass by? e.g. $2\mathrm{MgO}$ in a balanced equation: The balancing number in front of the formula, e.g. $2 \times 40 = 80$ .
Can a reacting mass calculation be done in tonnes or kilograms instead of grams?: Yes — the mass ratio is the same in any unit, as long as both masses use the same unit.
True or false? In $2\mathrm{Mg} + \mathrm{O_2} \rightarrow 2\mathrm{MgO}$ , 2 g of magnesium forms 2 g of magnesium oxide.: False. The oxide also contains the oxygen that reacted, so its mass is greater than the mass of magnesium.