Other Chemistry Answers

How many grams of NaN₃ are required to produce 12.0 ft³ of N₂ if the gas has a

          density of 1.25g/L?

How many grams of NaN₃ are required to form 1.00 g N₂?

An aqueous solution containing iron (II) (Fe²⁺) at a concentration of 2.5 x 10^-3 mg cm^-3 is subjected to the above treatment and measures an absorbance of 0.524. A water sample of unknown iron (II) (Fe²⁺) concentration is similarly treated and measures an absorbance of 0.350. Calculate the concentration of iron (II) (Fe²⁺) in the unknown sample in mg cm^-3.

Calculate the amount of Calcium chloride dihydrate in grams needed to make a 250 mL solution with a final Normality of 2,000 meq/L. Round answer to the nearest hundredth. 

Calculate the amount of Calcium chloride dihydrate in grams needed to make a 250 mL solution with a final Normality of 2,000 meq/L

Lesson 14 7.Aluminum oxide is decomposed using electricity to produce aluminum metal. How many grams of aluminum metal can be produced from 100.0 g of Al₂O₃?

2Al2O3 = 4Al + 3O2

8.Predict the mass of hydrogen gas produced when 2.73 g of aluminum reacts in a single replacement reaction with excess sulphuric acid.

2Al + 3H2SO4 = 3H2 + Al2(SO4)3

Lesson 14 question number 4.Solutions of iron (III) chloride, FeCl₃, are used in photoengraving and to make ink. This compound can be made by the following reaction: 2Fe + 3Cl2 = 2FeCl3

a. How many grams of Fe are needed to combine with 4.5 moles of Cl₂?

b. If 240 g of Fe is to be used in this reaction, with adequate Cl₂, how many moles of FeCl₃ will be produced?

5.Ammonia is produced synthetically by the reaction below. How many moles of NH₃ are formed when 200.0 g of N₂reacts with hydrogen?

N2 + 3H2 = 2NH3

6.Iron metal is produced in a blast furnace by the reaction of iron (III) oxide and coke (pure carbon). If 25.0 moles of pure Fe₂O₃ is used, how many grams of iron can be produced? The balanced chemical equation for the reaction is: Fe2O3 + 3C = 2Fe + 3CO

Lesson 14 Stoichiometry Problems

1. The compound KClO₃ decomposes according to the following equation: 2KClO3 = 2KCl + 3O2

a. What is the mole ratio of KClO₃ to O₂ in this reaction?

b. How many moles of O₂ can be produced by letting 6.0 moles of KClO₃ react based on the above equation?

c. How many molecules of oxygen gas, O₂, are produced in question 1b?

2.Magnesium combines with chlorine, Cl₂, to form magnesium chloride, MgCl₂, during a synthesis reaction.

a.Write a balanced chemical equation for the reaction.

b. How many moles of magnesium chloride can be produced with 3 moles of chlorine

3.Ethanol burns according to the following equation. If 15.0 mol of C₂H₅OH burns this way, how many moles of 

oxygen are needed?

C2H5OH + 3O2 = 2CO2 + 3H2O

What are the mole ratio and the mass ratio for H2O to O2 in the reaction 2H2 + O2 → 2H2O?

Lesson 12. Questions 1 to 5—convert the following number of moles to number of particles:

1. 2.0 moles of CaCl₂
2. 1.5 moles of copper(II) ions
3. 0.01 moles of H₂O
4. 5.0 moles of gold atoms
5. 0.0025 moles of HCl
6. What is the mass of 1 mole of Mg atoms?
7. What is the molar mass of aluminum?
8. What is the mass of 1 mole of oxygen atoms?
9. What is the mass of 1 mole of oxygen molecules, O₂?
10. Calculate the molar mass of NaOH.
11. What is the mass of 1.0 mole of CaCl₂?
12. Calculate the molar mass of Cu(NO₃)₂.
13. Calculate the molar mass of Al₂(SO₄)₃.