Stoichiometry

How many grams are in a mole of a substance?

• 22.4

• 1

• molar mass

• 6.02 x 10^23

Where does the mole ratio come from?

• The coefficients

• Always 1 to 1

• The subscripts

• The question

For the Balanced Reaction: 3 Mg + 1 Fe₂O₃ → 3 MgO + 2 Fe; What is the Ratio of moles of MgO to moles Fe?

• 3mol Mg / 2 mol Fe

• 2 mol Mg/ 3 mol Fe

• 1 mol Fe/ 2 mol Fe

• 3 mol MgO / 2 mol Fe

Tags

NGSS.HS-PS1-7

What is the mole ratio of HCl to CaCl₂ in this reaction: Ca(OH)₂ + 2 HCl --> CaCl₂ + 2 H₂O

• 2:2

• 1:1

• 1:2

• 2:1

Tags

NGSS.HS-PS1-7

A white powder used in paints, enamels and ceramics has the following mass percentage composition: Ba, 69.6% ; C, 6.09% and O, 24.3%. What is its empirical formula? (M_Ba = 137.3gmol^-1, M_C = 12.01gmol_-1, M_O = 16.00gmol^-1)

• BaCO₂

• Ba₂CO₂

• BaCO₃

• Ba₂CO₃

Tags

NGSS.HS-PS1-1

What volume of 0.500 mol dm⁻³ HCl(aq) is required to react completely with 10.0 g of calcium carbonate according to the equation below? CaCO₃(s) + 2HCl(aq) → CaCl₂(aq) + H₂O(l) + CO₂(g)

Tags

NGSS.HS-PS1-7

Using the following equation:
Fe₂O₃(s) + 3H₂(g) → 2Fe(s) + 3H₂O(l)
How many moles of iron can be made from  6 moles H₂? 

• 4 moles Fe

• 6 moles Fe

• 9 moles Fe

• 2 moles Fe

Tags

NGSS.HS-PS1-7

2H₂  +   O₂  →  2H₂O
How many moles of oxygen are consumed if 8 moles H₂ are used?

• 2

• 4

• 6

• 8

Tags

NGSS.HS-PS1-7

What is the mass of 2.6mol Lithium Bromide (LiBr)?

• 206g LiBr

• 2.6 mol LiBr

• 304g LiBr

• 226.2gLiBr

What is the stoichiometric coefficient of oxygen in the balanced equation for the combustion of propane: @@C_3H_8 + 5O_2 ightarrow 3CO_2 + 4H_2O@@?

• 3

• 4

• 5

• 6