List five ways you use chemistry at home or school ?
1 answer:
You might be interested in
Answer:
a)
b)
c)
d)
Explanation:
For neutral atoms:
Atomic Number (Z)= number of protons = number of electrons
Mass number (A) = number of protons + number of neutrons
For ions with positive net charge:
Number of protons = Z + net charge
For ions with negative net charge:
Number of protons= Z - net charge
a) A = 71, Charge = +3
Number of electrons = 28
Number of protons = 28 +3 =31
b) A = 35, Z = 45+35=80, Charge = -1
Number of protons =35
Number of neutrons = 45
Number of electrons = 36
Charge = Number of protons- Number of electrons =35-36 = -1
c) Charge = +4
Number of electrons = 86
Number of protons = Z = 86+4 = 90
mass number = A = 90+142 = 232
d) Charge = +2
Atomic number = Number of protons = Z = 38
mass number = A = 87
Answer : The percent yield is, 83.51 %
Solution : Given,
Mass of Zn = 5.00 g
Mass of = 25.00 g
Molar mass of Zn = 65.38 g/mole
Molar mass of = 168.97 g/mole
Molar mass of Ag = 107.87 g/mole
First we have to calculate the moles of Zn and .
Now we have to calculate the limiting and excess reagent.
The balanced chemical reaction is,
From the balanced reaction we conclude that
As, 2 mole of react with 1 mole of
So, 0.1479 moles of react with
moles of
From this we conclude that, is an excess reagent because the given moles are greater than the required moles and
is a limiting reagent and it limits the formation of product.
Now we have to calculate the moles of
From the reaction, we conclude that
As, 2 mole of react to give 2 mole of
So, 0.1479 moles of react to give 0.1479 moles of
Now we have to calculate the mass of
Theoretical yield of = 15.95 g
Experimental yield of = 13.32 g
Now we have to calculate the percent yield.
Therefore, the percent yield is, 83.51 %