Answer:
0.3
Explanation:
if I'm wrong don't mark it against me
Answer:
Precision refers to how close two or more measurements are to each other, regardless whether those measurements are accurate or not.
Accuracy refers to how closely the measured value of a quantity corresponds to its “true” value.
Explanation:
Answer:
10.10
Explanation:
Step 1: Write the basic dissociation reaction for pyridine
C₅H₅N(aq) + H₂O(l) ⇌ C₅H₅NH⁺(aq) + OH⁻(aq) Kb = 1.9 × 10⁻⁹
Step 2: Calculate [OH⁻]
For a weak base, we will use the following expression.
[OH⁻] = √(Cb × Kb) = √(9.2 × 1.9 × 10⁻⁹) = 1.3 × 10⁻⁴ M
Step 3: Calculate pOH
We will use the definition of pOH.
pOH = -log [OH⁻] = -log 1.3 × 10⁻⁴ = 3.9
Step 4: Calculate pH
We will use the following expression.
pH = 14 - pOH = 14 - 3.9 = 10.10
The mole fraction of solute in a 3.87 m aqueous solution is 0.0697
<h3>
calculation</h3>
molality = moles of the solute/Kg of the solvent
3.87 m dissolve in 1 Kg of water= 1000g
find the moles of water= mass/molar mass
that is 1000 g/ 18 g/mol= 55.56 moles
mole of solute = 3.87 moles
mole fraction is = moles of solute/moles of solvent
that is 3.87/ 55.56 = 0.0697
Al₂O has a higher percentage of aluminium.
Explanation:
To solve this problem, we have to compare the molar mass of the aluminium in each compound to one another as percentage of the whole compound:
Molar mass of Al₂O = 2(27) + 16 = 70g/mol
Molar mass of Al(NO₃)₃ = 27 + 3[14 + 3(16)] = 213g/mol
Percentage by mass of Al in Al₂O = 
x 100 = 77%
Percentage by mass of Al in Al(NO₃)₃ = 
x 100 = 12.7%
Al₂O has a higher percentage of aluminium.
learn more:
Molar mass brainly.com/question/2861244
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