Answer:
Please find the answer to the question below
Explanation:
In chemistry, the following mathematical formula is used to calculate the number of moles contained by a substance:
mole = mass of substance (g)/molar mass of substance (g/mol)
Molar mass of salicylic acid (C7H6O3) = 12(7) + 1(6) + 16(3)
= 84 + 6 + 48
= 138g/mol
Mass = 5.50grams
mole = 5.5/138
mole = 0.039
Approximately, the number of moles of 5.5grams of salicylic acid is 0.04moles. This is in accordance with the mole value (0.04) given in this question.
<span>Copper metal (Cu) reacts with silver nitrate (AgNO3) in aqueous solution to form Ag and Cu(NO3)2. An excess of AgNO3 is present. The balanced chemical equation is shown below.
Cu + 2AgNO3 ---> Cu(NO3)2 + 2Ag
The molar mass of Cu is 63.5 g/mol. The molar mass of Ag is 107.9 g/mol. What mass, in grams, of Ag is produced from reaction of 31.75 g of Cu?
26.95
107.9
215.91
431.82</span>
The equation is balanced as follows
Mgcl2 +2AgNo3 -->2Agcl +Mg(No3)2
from equation above 1 mole of MgCl2 reacted with 2 moles of AgNo3 to form 2 moles of AgCl2 and 1 mole of Mg(NO3)2
when balancing equation the number of atom of element should be the same on each side of equation.
