<span>3.75 gallons need to be drained and replaced with bleach.
Change the problem to "What amounts of a 100% solution and a 4% solution is needed to make 90 gallons of a 8% solution?" Given that, we'll use the following values.
x = amount of 4% solution.
90-x = amount of a 100% solution.
The equation to solve then becomes.
0.04 x + (90-x) = 0.08 * 90
0.04 x + 90 - x = 7.2
Add x to both sides
0.04x + 90 = 7.2 + x
Subtract 0.04x from both sides
90 = 7.2 + 0.96x
Subtract 7.2 from both sides
82.8 = 0.96x
Divide both sides by 0.96
86.25 = x
So you now know that you need 86.25 gallons of the original 4% solution and (90-86.25) = 3.75 gallons of the bleach to make the desired 90 gallons.
So simply drain 3.75 gallons from the tank and replace with bleach.</span>
Answer:
1. How did life begin?
2. Are we alone in the universe?
3. What makes us human?
Density is a ratio between the mass and the volume of a substance.It measures how much of a substance is packed into a set volume. Density increases when a larger amount of material is packed into a smaller volume. The same is true in opposite: density decreases when a smaller amount of a substance is packed into a larger volume.
To calculate density, we will take the total given mass of the substance and divide it by the total volume of its container.
In this problem, we have a mass of 86 grams and a volume of 25cm^3.
Density= mass/volume
Substitute the given values into the formula:
Density=86 grams/25 cm^3
Density=3.44 grams/cm^3
The density of the material is 3.44 g/cm^3.
Answer:
2.05 × 10²³ formula units
Explanation:
Given data:
Mass of AgF = 43.15 g
Number of formula units = ?
Solution:
Number of moles of AgF:
Number of moles = mass/ molar mass
Number of moles = 43.15 g/ 126.87 g/mol
Number of moles = 0.34 mol
Now Number of formula units will be determine 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
1 mole = 6.022 × 10²³ formula units
0.34 mol × 6.022 × 10²³ formula units
2.05 × 10²³ formula units