Answer:
8.0 × 10²¹ atoms contain 1.33 × 10⁻² moles.
Explanation:
The given problem will solve by using Avogadro number.
It is the number of atoms , ions and molecules in one gram atom of element, one gram molecules of compound and one gram ions of a substance.
The number 6.022 × 10²³ is called Avogadro number.
For example,
18 g of water = 1 mole = 6.022 × 10²³ molecules of water
1.008 g of hydrogen = 1 mole = 6.022 × 10²³ atoms of hydrogen
Given data:
Number of atoms = 8.0 × 10²¹ atoms
Number of moles = ?
Solution:
One mole of Cu = 6.022 × 10²³ atoms
For 8.0 × 10²¹ atoms:
(1 mol / 6.022 × 10²³ atoms)×8.0 × 10²¹ atoms
1.33 × 10⁻² moles
So, 8.0 × 10²¹ atoms contain 1.33 × 10⁻² moles.
Explanation:
It is given that aluminium nitrate and calcium chloride are mixed together with sodium phosphate.
And, 
Let us assume that the solubility be "s". And, the reaction equation is as follows.
s = 
Also, 
s = 
This means that first, aluminium phosphate will precipitate.
Now, we will calculate the concentration of phosphate when calcium phosphate starts to precipitate out using the 
expression as follows.
![K_{sp} = [Ca^{2+}]^{3}[PO^{3-}_{4}]^{2}](https://tex.z-dn.net/?f=K_%7Bsp%7D%20%3D%20%5BCa%5E%7B2%2B%7D%5D%5E%7B3%7D%5BPO%5E%7B3-%7D_%7B4%7D%5D%5E%7B2%7D)
![2.0 \times 10^{-29} = (0.016)^{3}[PO^{3-}_{4}]^{2}](https://tex.z-dn.net/?f=2.0%20%5Ctimes%2010%5E%7B-29%7D%20%3D%20%280.016%29%5E%7B3%7D%5BPO%5E%7B3-%7D_%7B4%7D%5D%5E%7B2%7D)
![2.0 \times 10^{-29} = 4.096 \times 10^{-6} \times [PO^{3-}_{4}]^{2}](https://tex.z-dn.net/?f=2.0%20%5Ctimes%2010%5E%7B-29%7D%20%3D%204.096%20%5Ctimes%2010%5E%7B-6%7D%20%5Ctimes%20%5BPO%5E%7B3-%7D_%7B4%7D%5D%5E%7B2%7D)
![[PO^{3-}_{4}]^{2}](https://tex.z-dn.net/?f=%5BPO%5E%7B3-%7D_%7B4%7D%5D%5E%7B2%7D)
= 
= 
M
Similarly, calculate the concentration of aluminium at this concentration of phosphate as follows.
![K_{sp} = [Al^{3+}][PO^{3-}_{4}]](https://tex.z-dn.net/?f=K_%7Bsp%7D%20%3D%20%5BAl%5E%7B3%2B%7D%5D%5BPO%5E%7B3-%7D_%7B4%7D%5D)
![9.84 \times 10^{-21} = [Al^{3+}] \times 2.21 \times 10^{-12}](https://tex.z-dn.net/?f=9.84%20%5Ctimes%2010%5E%7B-21%7D%20%3D%20%5BAl%5E%7B3%2B%7D%5D%20%5Ctimes%202.21%20%5Ctimes%2010%5E%7B-12%7D)
![[Al^{3+}] = 4.45 \times 10^{-9}](https://tex.z-dn.net/?f=%5BAl%5E%7B3%2B%7D%5D%20%3D%204.45%20%5Ctimes%2010%5E%7B-9%7D)
M
Thus, we can conclude that concentration of aluminium will be 
M when calcium begins to precipitate.
Answer:
.67 L
Explanation:
.030 mol x 22.4 L / 1 mol = .67 L
22.4 was used because that is what 1 mol equals for a gas at stp.
Complete Question:
A soccer player pumps air into a soccer ball until no more air can be pushed inside.Use the particle model to predict what will happen if a sharp object creates a hole in the soccer ball.
Answer:
particles will rush out of the ball until the pressure is equal inside and outside the ball
Explanation:
We need to understand when a ball is pumped with air until no more air can be pushed inside, that the particles inside the ball are closer together and bounce into each other more than the particles outside the ball and this makes the pressure inside the ball greater than that outside.
Now when a sharp object creates a hole in the soccer ball the particle move from a place of high pressure to a place of lower pressure because the force at the place of high pressure overpowers the force at the place of lower pressure.
Answer:
B. Granite
Explanation:
The continental crust is thicker, 30 km (20 mi) to 50 km (30 mi) thick. It is mostly made of less dense, more felsic rocks, such as granite.
