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S_A_V [24]
3 years ago
5

The forensic technician at a crime scene has just prepared a luminol stock solution by adding 10.0 g of luminol into a total vol

ume of 75.0 mL of H2O . What is the molarity of the stock solution of luminol
Chemistry
1 answer:
Murrr4er [49]3 years ago
8 0

Answer:

0.753M

Explanation:

Molecular formula of luminol is as follows: C8H7N3O2

Molecular formula of the luminol (C8H7N3O2) = 12(8) + 1(7) + 14(3) + 16(2)

= 96 + 7 + 42 + 32

= 177g/mol

mole of luminol = mass/molar mass

mole = 10 ÷ 177

mole = 0.0565 mol

Molarity can be calculated using the formula: Molarity = mol/volume (L)

Volume of water = 75.0 mL = 75/1000

= 0.075L

Molarity (M) = 0.0565 ÷ 0.075

The molarity of the stock solution = 0.753M

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Mariulka [41]

When a volume of 60.0 mL of 0.200 M HBr is mixed with a volume of 30.0 mL of 0.400 M CH3NH2, The pH value is mathematically given as

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<h3>What is the pH value when 60.0 mL of 0.200 M HBr is mixed with 30.0 mL of 0.400 M CH₃NH₂?</h3>

Question Parameters:

The pH when 60.0 mL of 0.200 M HBr

30.0 mL of 0.400 M CH₃NH₂ (Kb = 4.4 × 10^{-4}).

Generally, the equation for the Chemical Reaction  is mathematically given as

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Therefore

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OH=3.36

In conclusion, The equation pH value

pH+OH=14

Therefore

pH+=14-3.36

pH=10.64

Read more about Chemical Reaction

brainly.com/question/11231920

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2 years ago
What is the shape of a molecule that has 3 atoms bonded to a central atom and no lone pairs of electrons?
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This very correct.

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