Number of moles is defined as the ratio of given mass in g to the molar mass.
The mathematical formula is:
Number of moles = 
(1)
Number of zinc atoms is equal to 
, by Avogadro number, number of moles can be calculated.
As, 1 mol=
atoms, hence,
= 0.2822 mol
Now, from formula (1), calculate mass in g (molar mass of zinc = 65.4 g/mol)
0.2822 mol = 
mass in g = 
= 18.45588 g
Thus, by rounding off the above number, it will come near about 19 g approximately.
Hence, option (C) is the correct answer.
Answer:
60%
Explanation:
M(NH4NO3) = 2*14 +4*1 +3*16 = 80 g/mol
M(3O) = 3*16 = 48 g/mol
(48/80) *100 % =60% oxygen by mass.
Answer:
plum pudding model .
Explanation:
the electrons were 'like plums embedded in a pudding'. Also called the Raisin Bread Model.
Answer:
z≅3
Atomic number is 3, So ion is Lithium ion (
)
Explanation:
First of all
v=f*λ
In our case v=c
c=f*λ
λ=c/f
where:
c is the speed of light
f is the frequency
Using Rydberg's Formula:
Where:
R is Rydberg constant=
z is atomic Number
For highest Energy:
n_1=1
n_2=∞
z≅3
Atomic number is 3, So ion is Lithium ion ()
