Answer:
Therefore it will take 7.66 hours for 80% of the lead decay.
Explanation:
The differential equation for decay is


Integrating both sides
ln A= kt+c₁

[
]
The initial condition is A(0)= A₀,


.........(1)
Given that the
has half life of 3.3 hours.
For half life
putting this in equation (1)

[taking ln both sides,
]

⇒k= - 0.21
Now A₀= 1 gram, 80%=0.8
and A= (1-0.8)A₀ = (0.2×1) gram = 0.2 gram
Now putting the value of k,A and A₀in the equation (1)




⇒ t≈7.66
Therefore it will take 7.66 hours for 80% of the lead decay.
Answer:
=154.8 J
Explanation:
The rise in temperature is contributed by the change in temperature.
Change in enthalpy = MC∅, where M is the mass of the substance, C is the specific heat capacity and ∅ is the change in temperature.
Change in temperature = 100.0°C-20.0°C=80°C
ΔH=MC∅
The specific heat capacity of gold= 0.129 J/g°C
ΔH= 15.0g×0.129J/g°C×80°C
=154.8 J
Answer:
(a) 5s. n = 5. Sublevel s, l = 0. Number of orbitals = 1
(b) 3p. n = 3. Sublevel p, l = 1. Number of orbitals = 3
(c) 4f. n =4. Sublevel f, l = 3. Number of orbitals = 7
Explanation:
The rules for electron quantum numbers are:
1. Shell number, 1 ≤ n
2. Sublevel number, 0 ≤ l ≤ n − 1
So,
(a) 5s. n = 5, shell number 5. Sublevel s, l = 0. Number of orbitals = 2l +1 = 1
(b) 3p. n = 3, shell number 3. Sublevel p, l = 1. Number of orbitals = 2l +1 = 3
(c) 4f. n =4, shell number 4. Sublevel f, l = 3. Number of orbitals = 2l +1 = 7
Answer:
Element
Explanation:
Each different kind of atom represents an atom. Elements like atoms are considered to be distinct substances that cannot be split into simpler substances. Such substances are known to be made up of just one kind of atom.
Like an atom, elements are made up of protons, neutrons and electrons. Both the protons and neutrons are found in the nucleus of the atom.