Answer:
Explanation:
1 Al = 26.98 AMU
3 Br = 239.7 AMU
AlBr3 = 266.69 AMU
Al = (26.98)/(266.69) = 10.1%
Br3 = (239.7)/(266.69) = 89.9%
Answer:
Approximately 4574.86 years
Explanation:
Hello,
To find the age of this sample, we should first of all convert the disintegration per minute to per year so that we can work on the same unit as our half life (T½), then we can find the disintegration constant and use it to find the year of the artifact.
Data;
T½ = 5730 years
Initial rate of radioactivity (No) = 15.3 disintegration per minute.
Current rate of radioactivity (N) = 8.8 disintegration per minute.
1 year = 525600 minutes
1 mins = 8.8 disintegration
525600mins = N disintegration
N = (525600 × 8.8) / 1
N = 4625280
1 mins = 15.3 disintegration
525600 mins = No
No = 8041680
But T½ = In2 / λ
λ = In2 / T½
λ = 0.693 / 5730
λ = 1.209×10⁻⁴ (this is the disintegration constant)
We can now find the how old the artifact is using our disintegration constant and other parameters.
In(N÷No) = -λt
In[4625280 / 8041680] = -(1.209×10⁻⁴ × t)
In[0.57516] = -1.209×10⁻⁴t
-0.5531 = -1.209×10⁻⁴ t
Solve for t
t = 0.5531 / 1.209×10⁻⁴
t = 4574.86 years
The artifact is approximately 4574.86 years
Answer:
atomic orbital
Explanation:
Atoms are made of three sub-atomic particles, electron, proton and neutron.
Protons and neutrons are present in the core of the atom in a very small zone called nucleus. Nucleus is positively charged.
Electrons are present around the nucleus. Electrons present outside the nucleus are also termed as electron cloud. Region outside the nucleus where probability of finding an electron is maximum is termed as atomic orbital. Four basic types of orbitals are present around the nucleus which are
s-orbital
p-orbital
d-orbital
f-orbital
Electrons present in same orbitals have same energy. Therefore, term is atomic orbital.
Answer:
Helium
Explanation:
Atomic radii vary in a predictable manner across the periodic table. As can be seen in the figures below, the atomic radius increases from top to bottom in a group and decreases from left to right over a period of time. Helium is therefore the smallest element, and francium is the largest.