MOLE: AMOUNT SINGLE ELEMENT IN MOLECULE

EXERCISE 

1.  How many F atoms are in 1 mole of CF₄?

2.    How many atoms of Cu are in 4.6 mol Cu(OH)₂?  ;   

3.    How many Cu atoms are in 25.7 g of Cu(OH)₂?                 

4.    How many O and H atoms are in 1g of water, H₂O  

  

5.    How many moles of potassium ions and bromide ions in 0.25 moles of KBr?; 

6.    How many moles of calcium ions and chloride ions in 2.5 moles of CaCl₂?                   

7.    How many moles of aluminium ions and sulphate ions in 2 moles of Al₂(SO₄)₃?  

8.    If you have 4.5 x 10²⁰ molecules of SnO₂, how many moles of O do you have?         

9.    How many moles of H are in 2.5 x 10²³ molecules of C₂H₆O?   ; 

  

10. How many atoms of C is in 2.5 x 10²³ molecules of C₂H₆O? 

VIDEO TUTORIAL : MOLE CONCEPT

ANSWER ALL QUESTION

Q#1: 
1 DOZEN BANANAS = ___ BANANAS
3 DOZEN CARS = ____ CARS
1 DOZEN CARBON ATOMS = ____  ATOMS

Q#2
1 MOLE BANANAS = 
2 MOLE CARS = 
1 MOLE Mg ATOMS = 
3 MOLE H ATOMS =

Q#3
1 MOLE COPPER SULPHATE =  ____ MOLECULES
1 MOLE WATER MOLECULES = ____ MOLECULES
3 MOLE WATER = ____ MOLECULES

Q#4
Which of the following has more atoms, 1 MOLE OF HYDROGEN ATOMS or 1 MOLE WATER?



      

VIDEO TUTORIAL : MOLE-AVOGADRO

MOLE : EXERCISES

Q1 :

Monosodium glutamate (MSG, NaC₅H₈NO₄) is a flavor enhancer. How many moles of each element in MSG are present in 1.00 gram of MSG?

Q2 :

A sample of ammonia, NH₃, weighs 30.0 g. Calculate the following quantities:

a) moles of NH₃           

b) number of NH₃ molecules

c) number of N atoms   

d) number H atoms


Q2 : 
I have 400.00 grams of water in a beaker.

a) What is the molar mass of water?

b) How many MOLES of water do I have in the beaker?

c) How many MOLES of hydrogen atoms do I have in the beaker?

d) How many MOLES of oxygen atoms do I have in the beaker?

e) If all of my hydrogen atoms were converted to hydrogen molecules (H₂), how many MOLES of hydrogen molecules would I have?

f) If all of my oxygen atoms were converted to oxygen molecules (O₂), how MOLES of hydrogen molecules would I have?

g) How many MOLECULES of water do I have in the beaker?

Q3: 

A sample of sodium carbonate weights 15.0 grams. Calculate the following quantities:

a) moles of sodium carbonate  

b) number of molecules sodium carbonate

c) moles of sodium ions           

d) number of sodium ions

e) moles of carbonate ions

f) number of carbonate ion


Q4: 

Which compound contains the most nitrogen atoms in a 25.0 gram sample? Is it ammonium chloride, ammonia, nitrogen dioxide, or dinitrogen trioxide?

MOLE : Calculate the Mass of a Single Atom or Molecule

MOLE: INFOGRAPHIC

C3 : 3.1-MOLE

In chemistry the mole is a fundamental unit in the Système International d'Unités, the SI system, and it is used to measure the amount of substance. This quantity is sometimes referred to as the chemical amount.

- Mole is the generally accepted SI unit for measuring the amount of substance

- Mole is abbreviated to mol

- Mole has the symbol n

Defination mole in terms of C-12

One mole is the amount of substance that contains the same number of particles as the number of atoms in exactly 12.00g of C-12.

12 g of carbon-12 atoms = 6.02 x 10²³ carbon atoms

6.022 x 10²³ is called the Avogadro number or Avogadro constant 

Avogadro's number is equal to 602,214,199,000,000,000,000,000 or more simply, 6.02214199 × 10 ²³ 

N_A is the symbol used to represent the Avogadro Number

Defination mole in terms of Avogadro’s constant, N_A
One mole is the amount of substance that contains Avogadro’s constant, N_A of particles.

1 mole of "ANYTHING" contains 6.022 x 10²³ entities.

1 mole of donuts contains 6.02 x 10²³ donuts

1 mole of H₂O contains 6.02 x 10²³ molecules

1 mole of nails contains 6.02 x 10²³ nails

1 mole of Fe contains 6.02 x 10²³ atoms

1 mole of cats contains 6.02 x 10²³ catss
1 mole of electrons contains 6.02 x 10²³ electrons

1 MOLE = 6.02 x 10²³ particles 
1 MOLE = Molar Mass in gram ( Ar @ Mr )
1 MOLE = Molar Volume gas ( S.T.P @ R.T.P )

1.0 mol of chlorine atoms ( Cl )
= 6.023x10²³ chlorine atoms
= 35.5 g Cl

1.0 mol of chlorine molecules ( Cl₂ )
= 6.023x10²³ chlorine molecules
= 2(35.5) g
= 71.0 g Cl₂
= 6.023x10²³ x 2 chlorine atoms

1.0 mol of calcium bromide
= 6.023x10²³ units of CaBr₂
= 200 g CaBr₂
= 6.023x10²³ calcium ions
= 6.023x10²³ x 2 bromide ions

  1.0 mol of ammonia, NH₃ contains 
1.0 mol of nitrogen atoms and 
3.0 mol of hydrogen atoms.

1.0 mol of phosphorus, P₄ contains 
4.0 mol of phosphorus atoms.                            

1.0 mol of Na₂SO₄^.10H₂O contains 
2.0 mol of natrium ions, 
1.0 mol of sulphur atoms, 
4.0 mol of oxygen atoms and 
10.0 mol of water molecules.

C3 : MOLE-MASS-NO.PARTICLE CONVERSIONS

Relationship between mole, mass, Ar @ Mr and no. of particles

SOURCE: http://elementlearning.com/

Converting Mass to Moles & Moles to Mass  (by using Mr @ Ar)

Converting Moles to Mass (multiply by the molar mass)

1. How many grams are in 2.4 moles of sulfur?
ans : 2.4 x  32 = 76.8 grams

2. How many grams are in 238 moles of arsenic?  
ans : 238 x 75   = 17,850 grams

3. How many grams are in 11.9 moles of chromium?  
ans : 11.9 x 52   = 618.8 grams

4. How many grams are in 88.1 moles of magnesium?  
ans : 88.1 x 24 = 2114.4 grams

5. How many grams are in 4.5 moles of sodium fluoride, NaF?  

ans : 4.5 x 42 = 189 grams

6. How many grams are in 0.02 moles of beryllium iodide, BeI₂?  

ans : 0.02 x  263   = 5.26 grams

7. How many grams are in 3.3 moles of potassium sulfide, K₂S?  

ans : 3.3 x 110    = 363.0 grams

Converting Mass to Moles (divide by the molar mass)

1. How many moles are in 15 grams of lithium?  
ans : 15 / 7 = 2.14 moles

2. How many moles are in 22 grams of argon?  
ans : 22 / 40 = 0.55 moles

3. How many moles are in 2.3 grams of phosphorus?  
ans : 2.3 / 31 = 0.074 moles

4. How many moles are in 10.5 grams of magnesium?  
ans : 10.5 / 24 = 0.438 moles

5. How many moles are in 68 grams of copper (II) hydroxide, Cu(OH)₂? 
ans : 68 / 99 = 0.69 moles

6. How many moles are in 98.3 grams of aluminum hydroxide, Al(OH)₃? 
ans : 98.3 / 78 = 1.26 moles

7. How many moles are in 9.54 grams of silicon dioxide, SO₂?
ans : 9.54 / 64 = 0.149 moles


Converting Number of Particles to Moles & Moles to Number of Particles 

Converting Moles to No.of atoms/molecules/ions (multiply by the N_A)

1. How many atoms in 3.0 moles of Ar?
ans : 3.0 x  6.02 x 10²³ = 1.806 x 10²⁴ atoms

2. How many atoms in 8.5 moles of Fe?
ans : 8.5 x  6.023 x 10²³ = 5.117 x 10²⁴ atoms

3. How many molecules in 2.0 moles of CO₂?
ans : 2.0 x  6.023 x 10²³ = 1.204 x 10²⁴ molecules
ans : no.of C atom = 1.204 x 10²⁴ x 2 = 

4. How many molecules in 1.8 moles of PCl₃?
ans : 1.8 x  6.023 x 10²³ = 1.0836 x 10²⁴ molecules

5. How many molecules in 2.5 mol aluminuim sulphate, Al₂(SO₄)₃
ans : 2.5 x  6.023 x 10²³ = 1.505 x 10²⁴ molecules

6. How many molecules in 0.25 mol of scandium(III) oxide, Sc₂O₃.
ans : 0.25 x  6.023 x 10²³ = 1.505 x 10²³ molecules

Converting Mass to Moles (divide by the N_A)

MOLE : EXAMPLE CALCULATION

MAP : MOLE CONCEPT

MOLE : PRACTICE

Mole Practice Problem : 1

1.       59 g of Hydrochloric Acid  = __________________________ moles

2.       0.46 moles of Sodium Hydroxide  = _____________________g

3.       35g of Sulfuric Acid = _______________________________ mol

4.       877 g of Potassium Permanganate  = ___________________ mol

5.       3.4 x 10²⁴ moles of Copper (II) Bromide = _________________g

6.       0.56 moles of Calcium Hydroxide = _____________________ g

7.       4.0 x 10^-23 g of Magnesium = __________________________ mol

8.       49 g of Dihydrogen Monoxide = ________________________ mol

9.       6.4 g of Iron (III) Chlorate = ____________________________ mol

10.   4.5 moles of Nitric Acid = ______________________________ g

11.   2.1 x 10^-10 g of Phosphorus Pentabromide = _______________ mol

12.   9.6 moles of Nickel (II) Sulfate = _________________________ g

13.   1.15 moles of Acetic Acid = _____________________________ g

14.   65.7 g of Silver Nitrate = ______________________________ mol

15.   0.25 moles of Strontium Phosphide = ____________________ g

C2 : 2.3-Naming Ionic Compounds

An important part of dealing with chemical compounds is knowing how to refer to them. Learn to name all ionic compounds, including simple binary compounds, compounds containing transition metals and compounds containing polyatomic ions.

An ionic compound is chemical compound in which ions a held together by ionic bond. Usually, the positive charged portion consists of metal cation and negatively charged portion is an anion or polyatomic ion

CATION :

All cations are derived from metal atoms ( Na⁺, Mg²⁺, Al³⁺ )except ammonium ion ; NH₄⁺ and hydronium ion, H₃O⁺

Many metals (particularly transition elements) can form more than one ion, each with particular charge ^. Example : Fe²⁺  :  iron(II),  Fe³⁺  :  iron(III) 

ANION

Name of anion takes the root of the nonmetal and add suffix “–ide”

Examples are oxide (O^2-), sulfide (S^2-), fluoride (F^-), chloride (Cl^-), bromide (Br^-), iodide (I^-), nitride (N^3-), hydride (H^-)

To name an ionic compound you simply need to find the names of the cation and anion present in the compound.

1. Identify the cation:
• The cation is always written first in the formula for an ionic compound.
2. Identify the anion:
• Cover up the cation. Everything that is leftover will be the anion.
3. Write the name of the ionic compound by writing the name of the cation followed by the name of the anion

Example 1: Write the correct name for the compound whose empirical formula is Na₂SO₄.

1. Na₂SO₄ is an ionic compound because it contains a metal (Na) and two non-metals (S and O).
2. Identify the cation:
• The cation will be the first element written: Na₂SO₄
  • sodium ion
3. Identify the anion:
• The anion will be everything leftover once the cation has been identified: Na₂SO₄
  • sulfate ion
4. The correct name for Na₂SO₄ is sodium sulfate. 

Example 2: Write the correct name for the compound whose empirical formula is (NH₄)₂CO₃.

1. Even though this compound is composed of only non-metals, it is still an ionic compound. (It starts with NH₄.)
2. Identify the cation:
• The cation will always be the first ion written.
  • This compound contains the only common polyatomic cation. (NH₄)₂CO₃
    • ammonium ion
3. Identify the anion:
• The anion will be everything leftover once the cation has been identified: (NH₄)₂CO₃
  • carbonate ion
4. The correct name for this compound is ammonium carbonate.

Example 3: Write the correct name for the compound whose empirical formula is SnO₂.

1. This compound is an ionic compound. It contains a metal (Sn) and a non-metal (O).
2. Identify the cation:
• The cation is always written first in the formula.
  • SnO₂
• Tin can form two different cations Sn²⁺ and Sn⁴⁺). You must correctly identify its charge.
  • The charges of the cation and the anions must exactly balance out.
  • Since there are two anions and each one has a 2- charge, there is a total negative charge of 4-. In order to balance out the negative charge, the single tin ion must have a 4+ charge.
    • tin (IV) ion
3. Identify the anion:
• The anion will be everything leftover once the cation has been identified.
• SnO₂
  • oxide ion
4. The correct name for the compound is tin (IV) oxide.

Further example :