Percent Composition
Empirical
Formula
Mole &
Avogadros Number
Molecular
Compounds
Molecular Formulas &
Stoichiometry
100
The percent by mass of each element in a compound is what?
What is Percent Composition
100
The smallest whole number ratio of atoms present in a substance is what?
What is Empirical Formula
100
The number of representative particles contained in one mole of a substance; Equal to 6.02 x 10^23 particles is what?
Avogadros Number
100
A compound that is composed of molecules is what?
What is Molecular compound
100
The portion of chemistry dealing with numerical relationships in chemical reactions; The calculation of quanitys of substances involved in chemical equations is what?
What is Stoichiometry
200
When 13.60g sample of a compound containing only magnesium and oxygen is decomposed, 5.40g of oxygen is obtained. What is the percent composition of this compound?
What is % Mg= 8.20g/13.60x100%= 60.3% %O= 5.40g/13.60gx100%=39.7% 60.3+39.1= 100%
200
The four steps to find an empirical formula is?
What is Percent to mass Mass to mole Divide by smallest Multiply till whole number
200
The amount of a substance that contains 6.02 X 10^23 representative particles of that substance is what?
What is Mole
200
How are the melting points and boiling points of molecular compounds usually different from those of ionic compounds?
What is molecular compounds tend to have lower melting points and boiling points than ionic compounds
200
What is the molecular formula of a compound that has an empirical formula of NO2 and a molar mass of 92.02g/mol
What is 14.01+31.98=45.99 : 92.02/45.99=2 N2O4
300
How do you find Percent composition?
What is Part/whole x 100
300
The empirical formula of a compound that consist of 79.29 % Magnesium and 27.8 % nitrogen by mass is ?
What is Mg 72.2g : 72.2/24.30=2.97 : 2.97/1.98=1.5x2=3.00 N 27.8g : 27.8/14.01=1.98 : 1.98/1.98=1x2=2.00 Mg3N2
300
A term used to refer to the mass of a mole of any substance is?
What is Molar Mass
300
What is two nonmetallic elements that are covalently bonded to each other?
What is A binary molecular compound
300
The molecular formula of a compound that has an empirical formula of NO2 and a molar mass of 92.02g/mol is??
What is 14.01+31.98=45.99 : 92.02/45.99=2 N2O4
400
The Mass of element divided by the mass of compound x 100% is?
What is % mass of element
400
A compound is 2.46%H, 39.1%s, 58.5%O. what is the empirical formula?
What is H 2.46g : 2.46/1.01=2.43 : 2.43/1.21=2.00 S 39.1g : 39.1/32.06=1.21 : 1.21/1.21=1.00 O 58.5g : 58.5/15.99=3.65 : 3.65/1.21=3.00 H2SO3
400
6.02x10^23 atoms is equal to what?
What is 1 mole
400
How do you write the formula of a molecular compound?
What is Use the prefixes in the name to tell you the subscript of each element in the formula. Then write the correct symbols for the two elements with the correct subscripts.
400
How is the molecular formula of a compound related to its empirical formula?
What is the molecular formula of a compound is either the same as its experimentally determined empirical formula, or it is a simple whole number multiple of its empirical formula.
500
Propane (C3H8), fuel commonly used in gas grills, is one of the compounds obtained from petroleum. Calculate the percent composition of propane.
What is %C= 36.0g/44.0gx100%=81.8% %H=8.0g/44.0gx100= 18%
500
Phosphoric acid is found in some soft drinks. A sample of phosphoric acid contains 0.3086 g of hydrogen, 3.161 g of phosphorus, and 6.531 g of oxygen. determine the empirical formula.
What is H .3086/1.01=.305/.102=3.00 P 3.161/30.97=.102/.102=1.00 O 6.531/15.99=.408/.102=4.00 H3PO4
500
Aluminum is often used for the structure of light weight bicycle frames. How many grams of Al are in 3.00 moles of Al?
What is 3 mol x26.98/1mol=80.7g
500
What information do prefixes in the name of a binary molecular compound tell you about the composition of the compound?
What is : It tells how many atoms of an element are present in each molecule of the compound.
500
what shows how many atoms of each element a molecule contains?
What is Molecular formula
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