A mole ratio is ratio between the amounts in moles of any two compounds involved in a chemical reaction.
100
What is molar mass?
the mass of a given substance or element
100
What is Percent Composition?
The percent of an element compared to the percent of other elements in a given compound.
100
The total amount of grams in a element or a compound is equal to how moles?
Explain.
1 mole
The total molar mass of a compound is equal to however many grams are in single mole it makes up.
100
How many molecules are in a single mole?
How is the solution expressed? ( give a written example)
6.02*10^23
Ex: 2.45 * 10^24
200
How many moles of H2O are in the chemical reaction.
O2 + 3H2O = 2H2O
What is the mole ratio of O2?
3 moles H2O
ratio =1:2
200
Give an example of how to find molar mass. (this can be written or explained.)
Molar mass is given by the atomic mass of an element. Once all atomic masses are found they are added together as so.
Ex. H2O H-1*2= 2 O= 16 2+16=18
H2O has a molar mass of 18
200
What is the first step in finding Percent Composition?
Find the molar mass
200
If you are given a specified amount of grams for a compound how to you find how many moles it has?
You divide the number of grams given by the number of grams originally in that compound also called molar mass.
200
Who found how many molecules where in a single mole?
DAILY DOUBLE
Where are they from?
Within a 11 year time period when was this theory proposed? (Extra 100 points)
Amedeo Avogadro
Turin,Italy
1810-1821
300
Verbally explain what is happening in this chemical reaction. Then give the ratio of H2.
N2 (g) + 3 H2 (g) --> 2 NH3 (g)
NH3 = ammonia
1 mole of Nitrogen reacts with 3 moles of Hydrogen to produce 2 moles of ammonia.
Ratio = 3:2
300
How do subscripts apply to molar mass? What if they are outside parenthesis? (written or explained)
They make the original atomic mass of an element multiply by two.
Ex. H2 H=1 * 2(subscript) = 2
If outside, the atomic mass of that element is multiplied by the subscript in the parenthesis (if prevalent). Then by the subscript outside of the parenthesis.
Ex. Mg(OH)2 Mg= 24.31 O= 32 H= 2
300
In percent composition what is divided by total molar mass?
What is it then multiplied by?
Why?
Molar mass of the specific element.
100
The total percentage of the compound is 100%
300
If you are given 34 grams of NH3 how many moles would you have?
Explain.
2 moles.
NH3 has a molar mass of 17g/mol. You are given 34 grams divided by the molar mass of 17 is 2 moles.
300
If given 10 moles of O2 how many molecules would you have?
Explain.
6.02*10^24
You have to multiply 10 * (6.02*10^23) so there for you get 6.02*10^24.
400
Give all mole ratios for NaCl + 3AgNO3 + 2AgCl + 3NaNO3
(written or verbal)
1 mole NaCl ; over 3 moles AgNO3, 2AgCl, 3NaNO3
3 moles AgNO3 ; over 2 moles AgCl, 3NaNO3
2 moles AgCl over 3 moles NaNO3
400
Give the atomic mass for Ga2(SO3)3
379.7
400
What is the percent composition of H in H2O?
Mass of Hydrogen= 1
Mass of Oxygen = 16
11.11%
400
How many grams are in 6 moles of H2O?
Explain.
108 grams
H2O has a molar mass of 18g/mol , you are given 6 moles of H2O. So 18 * 6 gives you 108 grams of H20
400
You have 3.2 moles of AuCl3 how many molecules do you have?
1.93*10^24
500
2 CH3OH (l) + 3 O2 (g) --> 2 CO2 (g) + 4 H2O (l)
For the following problem if 6 moles of CH3OH are burned how many moles of H2O are formed?
(written)
12 moles H2O
500
In what two units can Molar mass be expressed? (must write out)
If you have one gram molar mass of a substance how many moles would you have?