Explanation:
a particle smaller than an atom (e.g., a neutron) or a cluster of such particles (e.g., an alpha particle).
Answer:
a. 82.68 g b. 9.8 min
Explanation:
a. The amount of gold deposited by 5 A current in 2 hrs 15 mins
Since charge Q = It where I = current = 5 A and time = 2 hrs 15 mins = 2 × 60 min + 15 min = 120 + 15 min = 135 min = 135 × 60 s = 8100 s
Q = 5 A × 8100 s
= 40500 C
Also, Q = nF where n = number of moles of gold deposited and F = Faraday's constant = 96500 C
n = Q/F = 40500 C/96500 C = 0.4195 moles ≅ 0.42 mole
Now n = m/M where m = mass of gold and M = molar mass of gold = 197
m = nM
= 0.42 × 197 g
= 82.68 g
b. The time taken for 6g of gold to be deposited.
We first find the number of moles of gold in 6g of gold
Since n = m/M and m = 6 g
n = 6/197 = 0.0305 mole
Q = It = nF
t = nF/I
= 0.0305 mol × 96500 C/5 A
= 2939.09 mol C
= 587.82 s
Changing t to minutes
587.82/60 s = 9.8 min
The electron configuration that represent an excited state for an atom of calcium is 2, 8, 7, 3.
Calcium atom has an atomic number of 20 and its electronic configuration is 2, 8, 8, 2. An atom is said to be in an excited state if it gains energy and move to an higher energy level. For the calcium atom given above, there are 20 electrons which are distributed into four shells. But in the excited state [option 3], one of the 8 electrons in the third shell gains energy and move to the fourth shell. Thus, the number of electrons in the third shell reduced by 1, while the number of electrons in the fourth shell increase by 1.
M₁V₁ = M₂V₂
(0.050M)*(10 mL) = (0.10M)*(x)
x = 5 mL
You would take 5 mL of the 0.10 M solution of HCl and add 5 mL of deionized water. Therefore, the total volume will be 10 mL and it will have a molarity of 0.050.