Answer: 50 nm
Explanation: Two steps:
1. Divide 3.25/6.5 = 0.5
2. Divide 10^8/10^6 = 10^2
nm^2/nm = nm
Combine: 0.5x10^2 nm
or 50 nm
Answer:
0.1 M
<h3>
Explanation:</h3>
- Molarity refers to the concentration of a solution in moles per liter.
- It is calculated by dividing the number of moles of solute by the volume of solvent;
- Molarity = Moles of the solute ÷ Volume of the solvent
<u>In this case, we are given;</u>
- Number of moles of the solute, NH₄Cl as 0.42 moles
- Volume of the solvent, water as 4200 mL or 4.2 L
Therefore;
Molarity = 0.42 moles ÷ 4.2 L
= 0.1 mol/L or 0.1 M
Thus, the molarity of the solution will be 0.1 M
Answer:
Three times with 5 ml will yield more
Explanation:
Let x represent the amount yield
Kd = (x/15) / ((50-x) / 15) where Kd = 1.5
1.5 = (x/15) / ((50-x) / 15)
x / (50 - x) = 1.5
x = 75 - 1.5x
x + 1.5x = 75
2.5x = 75
x = 75 / 2.5 = 30 mg
when extraction three times
1st extraction
(x1/5) / ((50 - x1) / 15) = 1.5
3x1 / 50 - x1 = 1.5
3x1 = 75 - 1.5x1
3x1 + 1.5x1 = 75
4.5x1 = 75
x1 = 75 / 4.5 = 16.67 gm
second extraction
(x2/ 5) / (33.33 - x2 ) / 15) = 1.5
3x2 / ( 33.33 - x2) = 1.5
3x2 = 1.5(33.33 - x2)
3x2 = 49.995 - 1.5x2
3x2 + 1.5x2 = 49.995
4.5x2 = 49.995
x2 = 49.995 / 4.5
x2 = 11.11 mg
Third extraction
(x3/5) / ((22.22 - x3) / 15) = 1.5
3x3 = 1.5 ( 22.22 - x3)
3x3 + 1.5x3 = 33.33
4.5x3 = 33.33
x3 = 33.33 / 4.5 = 7.41 mg
total extraction = x1 + x2 + x3 =16.67 + 11.11 + 7.41 = 35.19 mg
the three times extraction using 5ml yields 5.19 mg more
Answer:
Q = -33.6kcal .
Explanation:
Hello there!
In this case, according to the equation for the calculation of the total heat of reaction when a fixed mass of a fuel like ethane is burnt, we can write:
Whereas n stands for the moles and the other term for the enthalpy of combustion. Thus, for the required total heat of reaction, we first compute the moles of ethane in 3 g as shown below:
Next, we understand that -337.0kcal is the heat released by the combustion of 1 mole of ethane, therefore, to compute Q, we proceed as follows:
Best regards!
Answer:
D.
Explanation:
The rock that is left behind is there because it has resisted the forces of erosion.
