Answer:
3.79 x 10²⁴atoms
Explanation:
Given parameters:
Number moles of lead = 6.3moles
Unknown:
Number of atoms = ?
Solution:
To solve this problem,
1 mole of a substance contains 6.02 x 10²³ atoms
6.3 mole of Pb will contain 6.3 x 6.02 x 10²³ = 3.79 x 10²⁴atoms
Answer:
Explanation:
Any densities less than 1g/cm3 will float, while objects with densities over 1g/cm3 will sink.
Almost all properties are common to elements within a single group on the periodic table. They react with water in the same way, they have the same number of valence electrons thereby having the same valency, the number of shells in the atom of the element increases by one as we move down the group.
In general, they have the same chemical properties as chemical properties depend on the number of electrons in the valence shell i.e. the outermost shell in the atom of an element.
Answer:
The second transformation is a rotation around (point) L.
Explanation:
Generally, a rigid transformation is used to change only the position of a figure while the shape remains the same. In order to map a triangle (ΔJKL) to another triangle (ΔMNQ), two rigid transformations were employed. In the first transformation, the vertex L was mapped to the vertex Q. Therefore, the second transformation will definitely involve the rotation around (point) L. This will complete the two rigid transformations.
<u>Answer:</u> The concentration of radon after the given time is 
<u>Explanation:</u>
All the radioactive reactions follows first order kinetics.
The equation used to calculate half life for first order kinetics:
We are given:
Putting values in above equation, we get:
Rate law expression for first order kinetics is given by the equation:
![k=\frac{2.303}{t}\log\frac{[A_o]}{[A]}](https://tex.z-dn.net/?f=k%3D%5Cfrac%7B2.303%7D%7Bt%7D%5Clog%5Cfrac%7B%5BA_o%5D%7D%7B%5BA%5D%7D)
where,
k = rate constant = 
t = time taken for decay process = 3.00 days
![[A_o]](https://tex.z-dn.net/?f=%5BA_o%5D)
= initial amount of the reactant = 
[A] = amount left after decay process = ?
Putting values in above equation, we get:
![0.181days^{-1}=\frac{2.303}{3.00days}\log\frac{1.45\times 10^{-6}}{[A]}](https://tex.z-dn.net/?f=0.181days%5E%7B-1%7D%3D%5Cfrac%7B2.303%7D%7B3.00days%7D%5Clog%5Cfrac%7B1.45%5Ctimes%2010%5E%7B-6%7D%7D%7B%5BA%5D%7D)
![[A]=3.83\times 10^{-30}mol/L](https://tex.z-dn.net/?f=%5BA%5D%3D3.83%5Ctimes%2010%5E%7B-30%7Dmol%2FL)
Hence, the concentration of radon after the given time is
