<u>Answer:</u> The amount of sample left after 20 years is 288.522 g and after 50 years is 144.26 g
<u>Explanation:</u>
We are given a function that calculates the amount of sample remaining after 't' years, which is:
Putting values in above equation:
Hence, the amount of sample left after 20 years is 288.522 g
Putting values in above equation:
Hence, the amount of sample left after 50 years is 144.26 g
The 28 is the sum of the protons and neutrons in the element silicon.
ALL silicon atoms have 14 protons in the nucleus, so we can turn this into an equation:
#protons + #neutrons = 28
14 + #neutrons = 28
#neutrons = 14
#protons = 14
This element is found in group 3A, period 3
<h3>Further explanation
</h3>
The maximum number of electrons that can be filled in the nth electron shell is 2n²(n=shell)
-
K shell (n = 1) maximum 2 x 1² = 2 electrons
- L shell (n = 2) maximum 2 x 2² = 8 electrons
- M shell (n = 3) maximum 2 x 3² = 18 electrons
- N shell (n = 4) maximum 2 x 4² = 32 electrons
Electron configuration of element X : 2.8.3 , so :
K shell = 2 ⇒1s²
L shell = 8⇒2s²2p⁶
M shell = 3⇒ 3s²3p¹
Block p: group 13-18 (has a 2p-6p configuration), also called a representative element because it includes metals, non-metals and metalloids
The outer shell 3s²3p¹ : located in group 3A and period 3
group⇒valence electron ⇒3
period⇒the greatest value of the quantum number n⇒3
The solution has a concentration 20 mgr in each mL of the final solution.
To solve this problem, we need to know about concentration. The concentration formula can be defined as how much the mass per unit volume is. It can be written as
M = m/V
where M is concentration, m is mass of solute, V is the total volume of solution.
From the text we know that :
m = 10g
vsolvent = 45mL
vsolute = 5 mL
find the total volume (V)
V = vsolvent + vsolute
V = 45 + 5
V = 50mL
Then, find the concentration
M = m/V
M = 10gr / 50 mL
M = 1000 mgr / 50mL
M = 20 mgr / mL
Hence, the solution has a concentration 20 mgr in each mL of the final solution.
Find more on concentration at: brainly.com/question/17206790
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