Moles of any substance is given by the molar mass and the mass. The volume of EDTA required to titrate is 3.16 mL and the volume of zinc required to titrate is 22.8 mL.
Molarity is the property of the solution that gives the concentration of the solute present in the solution.
Given,
Mass of cobalt sulfate = 1.697 gm
The molar mass of cobalt sulfate = 155 g/mol
In the first part, the volume of the aliquot is 25 mL and the molarity is 0.08640 M.
The reaction is shown as:
Co²⁺ + H₄Y → CoH₂Y + 2H⁺
Moles of cobalt: n = 0.001694 ÷ 155 = 0.0000109 moles
In 25 ml aliquot moles of cobalt are, 0.000273 moles.
The volume of EDTA solution is calculated as:
V = moles ÷ Molarity
= 0.000273 mole ÷ 0.0864 mol/ L
= 3.16 mL
Hence, 3.16 mL of EDTA is required.
For the second part, moles of EDTA are calculated as:
n = 0.008640 × 0.050 = 4.32 ×10⁻⁴
In a 25 mL, sample moles of EDTA are 2.16 × 10⁻⁴ moles.
Excess moles of EDTA in the solution:
0.000432 - 0.000216 = 0.000216 moles
The volume of EDTA is calculated as:
V = 0.000216 ÷ 0.009450
= 0.0228 L
Hence, 22.8 mL of zinc is required.
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Answer:
the answer is in the screenshot
Explanation:
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b. 26.0 g H2SO4 in 200.0 mL solution
c. 15.0 g NaCl dissolved to make 420.0 mL solution
Answer:
a) NaHCO3 = 0.504 M
b) H2SO4 = 1.325 M
c) NaCl = 0.610 M
Explanation:
Step 1: Data given
Moles = mass / molar mass
Molarity = moles / volume
a. 19.5 g NaHCO3 in 460.0 ml solution
Step 1: Data given
Mass NaHCO3 = 19.5 grams
Volume = 460.0 mL = 0.460 L
Molar mass NaHCO3 = 84.0 g/mol
Step 2: Calculate moles NaHCO3
Moles NaHCO3 = 19.5 grams / 84.0 g/mol
Moles NaHCO3 = 0.232 moles
Step 3: Calculate molarity
Molarity = 0.232 moles / 0.460 L
Molarity = 0.504 M
b. 26.0 g H2SO4 in 200.0 mL solution
Step 1: Data given
Mass H2SO4 = 26.0 grams
Volume = 200.0 mL = 0.200 L
Molar mass H2SO4 = 98.08 g/mol
Step 2: Calculate moles H2SO4
Moles H2SO4 = 26.0 grams / 98.08 g/mol
Moles H2SO4 = 0.265 moles
Step 3: Calculate molarity
Molarity = 0.265 moles / 0.200 L
Molarity =1.325 M
c. 15.0 g NaCl dissolved to make 420.0 mL solution
Step 1: Data given
Mass NaCl = 15.0 grams
Volume = 420.0 mL = 0.420 L
Molar mass NaCl = 58.44 g/mol
Step 2: Calculate moles NaCl
Moles NaCl = 15.0 grams / 58.44 g/mol
Moles NaCl = 0.256 moles
Step 3: Calculate molarity
Molarity = 0.256 moles / 0.420 L
Molarity =0.610 M
Explanation:
Solubility is a chemical property referring to the ability for a given substance, the solute, to dissolve in a solvent. It is measured in terms of the maximum amount of solute dissolved in a solvent at equilibrium. The resulting solution is called a saturated solution.
moles?
765.75
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music for three hours each day. Plant D does not listen to any music at all.
1. Based on the experiment in the scenario, which visual aid would be most helpful in showing the change in the plants' heights over time?
O A. A line graph
O B. A pie chart
OC. A bar graph
O D. A timeline
Answer:
A. A line graph
Explanation:
You use line graphs to track changes over time. Line graphs are better when the changes are small. They are also more useful when you want to compare changes over the same period for more than one group, for example, plants exposed to music and a control group.
B is wrong. A pie chart is best for comparing parts of a whole.
C is wrong. You can use a bar graph to track changes over time, but small changes are harder to spot.
D is wrong. You use a timeline to mark important points in time, for example, when you are deciding the times when you must complete various stages of a project.
Which of the charts below do you think is more helpful in showing the change in plant height over time?
Which of the following statements are correct?
Choose all that apply.
ΔGo > 0
The reaction is product-favored.
K < 1
Eocell > 0
n = 2 mol electrons
B-
Answer:
Eªcell > 0; n = 2
Explanation:
The reaction:
I2 (s) + Pb (s) → 2 I- (aq) + Pb2+ (aq)
Is product favored.
A reaction that is product favored has ΔG < 0 (Spontaneous)
K > 1 (Because concentration of products is >>>> concentration reactants).
Eªcell > 0 Because reaction is spontaneous.
And n = 2 electrons because Pb(s) is oxidizing to Pb2+ and I₂ is reducing to I⁻ (2 electrons). Statements that are true are: