Determine the percentage composition of each of the following compounds
a) NaCl
b) AgNO3
c) Mg(OH)2
for NaCl i got na=23/135=0.17 x 100= 17% Cl=35/135=0.26 x 100=26%
for AgNO3 i got 108/42 which im sure was wrong and i didn't get how to complete the problem..
for Mg(OH)2 i didn't have a clue
please help!
thanks in advance
To determine the percentage composition of a compound, we need to find the mass percent of each element in the compound. The mass percent of an element is the mass of the element divided by the molar mass of the compound, multiplied by 100.
a) NaCl:
NaCl consists of sodium (Na) and chloride (Cl) ions. To find the percentage composition of NaCl, we need to know the molar mass of NaCl. The molar mass can be calculated by adding the atomic masses of Na (sodium) and Cl (chlorine).
Molar mass of NaCl = 22.99 g/mol (Na) + 35.45 g/mol (Cl) = 58.44 g/mol
Now let's calculate the mass percent of each element:
Mass percent of Na = (mass of Na / molar mass of NaCl) * 100
Mass percent of Na = (22.99 g/mol / 58.44 g/mol) * 100 = 39.34%
Mass percent of Cl = (mass of Cl / molar mass of NaCl) * 100
Mass percent of Cl = (35.45 g/mol / 58.44 g/mol) * 100 = 60.66%
Therefore, the percentage composition of NaCl is 39.34% Na and 60.66% Cl.
b) AgNO3:
AgNO3 consists of silver (Ag), nitrogen (N), and oxygen (O) atoms. The molar mass of AgNO3 can be calculated by summing the atomic masses of Ag, N, and O.
Molar mass of AgNO3 = (107.87 g/mol (Ag) + 14.01 g/mol (N) + (16.00 g/mol (O) * 3) = 169.87 g/mol
Now let's calculate the mass percent of each element:
Mass percent of Ag = (mass of Ag / molar mass of AgNO3) * 100
Mass percent of Ag = (107.87 g/mol / 169.87 g/mol) * 100 = 63.46%
Mass percent of N = (mass of N / molar mass of AgNO3) * 100
Mass percent of N = (14.01 g/mol / 169.87 g/mol) * 100 = 8.24%
Mass percent of O = (mass of O / molar mass of AgNO3) * 100
Mass percent of O = (16.00 g/mol * 3 / 169.87 g/mol) * 100 = 28.30%
Therefore, the percentage composition of AgNO3 is 63.46% Ag, 8.24% N, and 28.30% O.
c) Mg(OH)2:
Mg(OH)2 consists of magnesium (Mg), hydrogen (H), and oxygen (O) atoms. The molar mass of Mg(OH)2 can be calculated by summing the atomic masses of Mg, H, and O.
Molar mass of Mg(OH)2 = (24.31 g/mol (Mg) + (1.01 g/mol (H) * 2) + (16.00 g/mol (O) * 2) = 58.33 g/mol
Now let's calculate the mass percent of each element:
Mass percent of Mg = (mass of Mg / molar mass of Mg(OH)2) * 100
Mass percent of Mg = (24.31 g/mol / 58.33 g/mol) * 100 = 41.68%
Mass percent of H = (mass of H / molar mass of Mg(OH)2) * 100
Mass percent of H = (1.01 g/mol * 2 / 58.33 g/mol) * 100 = 3.46%
Mass percent of O = (mass of O / molar mass of Mg(OH)2) * 100
Mass percent of O = (16.00 g/mol * 2 / 58.33 g/mol) * 100 = 54.86%
Therefore, the percentage composition of Mg(OH)2 is 41.68% Mg, 3.46% H, and 54.86% O.
I don't understand what you are asking for. Do you want the percent by mass of each element in the compound? Or by atom or mole? For example, NaCl is clearly 50% Na by ATOM. By mass, Na is 23.0 of the total molar mass of 58.5, or 39.3%
Do the others the same way, if that is what the question is all about.