6. Chemical Reactions & Quantities

The oxidation of chromium solid is represented by the following equation:

4 Cr (s) + 3 O₂ (g) → 2 Cr₂O₃ (s)

How many moles of chromium (III) oxide are produced when 34.69 g Cr reacts with excess oxygen gas? 

The reaction of potassium chlorate and sucrose is given below:

8 KClO₃ + C₁₂H₂₂O₁₁ → 8 KCl + 12 CO₂ + 11 H₂O

If 2.33 x 10^-7 formula units of potassium chlorate are reacted, how many grams of carbon dioxide will be produced? 

If the density of ethanol, CH₃CH₂OH, is 0.789 g/mL, how many milliliters of ethanol are needed to produce 4.8 g of H₂O in the following reaction?

CH₃CH₂OH (l) + 3 O₂ (g) → 3 H₂O (l) + 2 CO₂ (g)

How many moles of NiCl₂ can be formed in the reaction of 6.00 mol of Ni and 12.0 mol of HCl?

Ni(s) + HCl(aq) → NiCl₂(aq) + H₂(g)

Balance the following equation, and tell how many moles of nickel will react with 9.81 mol of hydrochloric acid.

Ni(s) + HCl(aq) → NiCl₂(aq) + H₂(g)

The following diagram represents the reaction of A₂(red spheres) with B₂(blue spheres):

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b. How many moles of product can be made from 1.0 mol of A₂? From 1.0 mol of B₂?

Titanium metal is obtained from the mineral rutile, TiO2. The process requires multiple steps, as shown in the following reactions:

TiO₂(s) + 2 Cl₂(g) + 2 C(s) → TiCl₄(s) + 2 CO(g)

TiCl₄(s) + 2 Mg(s) → Ti(s) + 2 MgCl₂(s)

a. Write mole ratios to show the relationship between the reactants and products for each reaction.