Answer:
44.63g
Explanation:
First, let us calculate the number of mole of KBr in 1.50M KBr solution.
This is illustrated below:
Data obtained from the question include:
Volume of solution = 250mL = 250/1000 = 0.25L
Molarity of solution = 1.50M
Mole of solute (KBr) =.?
Molarity is simply mole of solute per unit litre of solution
Molarity = mole /Volume
Mole = Molarity x Volume
Mole of solute (KBr) = 1.50 x 0.25
Mole of solute (KBr) = 0.375 mole
Now, we calculate the mass of KBr needed to make the solution as follow:
Molar Mass of KBr = 39 + 80 = 119g/mol
Mole of KBr = 0.375 mole
Mass of KBr =?
Mass = number of mole x molar Mass
Mass of KBr = 0.375 x 119
Mass of KBr = 44.63g
Therefore, 44.63g of KBr is needed to make 250.0mL of 1.50 M potassium bromide (KBr) solution
1. B
2. H
3. G
4. I
5. D
6. C
7. A
8. F
9. E
I am not sure weather it is correct but I wrote what I know
Answer:
A
Explanation:
You want an equation that includes both V and T. Charles' Law states that V =kT or V₁/T₁ = V₂/T₂, so this is the best formula to use.
B: The Combined Gas Law is p₁V₁/T₂ = p₂V₂/T₂ will work, but it's overkill for the situation. You can assume any constant value for the pressure, and it will cancel from each side of the equation,
C is wrong. Boyle's Law is p₁V₁ = p₂V₂. It does not include the temperature.
D is wrong. Gay-Lussac's Law is p₁/T₂ = p₂/T₂. It does not include the volume.
PH scale is used to determine how acidic or basic a solution is.
pH can be calculated as follows;
by knowing the ph we can calculate pOH
pH + pOH = 14
pOH = 14 - 8.1
pOH = 5.9
pOH is used to calculate the hydroxide ion concentration
pOH = -log[OH⁻]
[OH⁻] = antilog(-pOH)
[OH⁻] = 1.26 x 10⁻⁶ M
therefore hydroxide ion concentration is 1.26 x 10⁻⁶ M
Answer:
energy
energy is the reason why people can do things
