Finally, sometimes the desired value does not directly match the units given but is derived from the calculation required. For e

Answer:

Explanation:

Hello,

In this scenario, since 11 mg of cyanide per kilogram of body weight is lethal for 50% of domestic chickens, we can determine the lethal amount for a chicken weighing 3 kg using a proportion:

Thus, we find:

Which equates to grams as follows:

Regards.

Answer:

The typical atomic weight of bromine is 79.9 amu.

Explanation:

Provided information:

Br⁷⁹ constitutes 55% of the sample

Br⁸¹ constitutes 45% of the sample

What is the average atomic weight of bromine?

Calculation formula:

Average atomic mass = [isotope mass × its proportion] + [isotope mass × its proportion] +...[ ] / 100

We can now insert the known values into the formula.

Average atomic mass = [55 × 79] + [81 × 45] / 100

Average atomic mass = 4345 + 3645 / 100

Average atomic mass = 7990 / 100

Average atomic mass = 79.9 amu

The typical atomic weight of bromine is 79.9 amu.

1. The luminol stock solution has a molarity of 1.431 M.

2. In 2.00 L of the diluted spray, there are 0.12 moles of luminol.

3. The volume of the stock solution from Part A that contains the same number of moles present in the diluted solution from Part B is 83.86 ml.

Additional Information

Stoichiometry in Chemistry focuses on the quantitative aspects of chemical reactions, which includes calculations related to volume, mass, and the count of ions, molecules, and elements.

Key concepts in stoichiometry include:

• 1. Relative atomic mass
• 2. Relative molecular mass

This refers to the relative atomic mass of a molecule.

• 3. Mole

A mole represents the number of particles in a substance equivalent to the number of atoms in 12 grams of carbon-12.

1 mole = 6.02 × 10²³ particles.

The quantity of moles can also be derived by dividing mass (in grams) by either the relative mass of an element or the relative mass of a molecule.

Luminol (C₈H₇N₃O₂) is utilized for detecting blood traces at crime scenes, due to its reaction with iron found in blood.

To prepare a luminol stock solution, 19.0 g of luminol is mixed into a total volume of 75.0 mL of water.

Thus, the molarity is calculated as:

• 1. Moles of Luminol

- the relative molecular mass of Luminol:

= 8.C + 7.H + 3.N + 2.16

= 8.12 + 7.1 + 3.14 + 2.16

= 177 grams/mol.

Thus, we have:

moles = grams / relative molecular mass.

moles = 0.1073.

2. Molarity (M)

M = moles / volume

M = 1.431.

• b. The concentration of luminol in the spray bottle is 6.00 × 10⁻² M. Therefore, in a 2 L solution, the number of moles is:

moles = M × volume

moles = 6 × 10⁻² × 2

moles = 0.12.

• c. The molarity of the stock solution (Part A) is 1.431 M.

The diluted solution (Part B) contains 0.12 moles of luminol.

To find the volume of the stock solution (Part A) that has the same moles as the diluted solution (Part B):

volume = moles / M

volume = 0.08386 L = 83.86 mL.

Further Learning

moles of water you can generate

the amount of each atom in the chemical's formula

the proportion of hydrogen to oxygen atoms in 2 L of water

Keywords: mole, volume, molarity, Luminol, relative molecular mass

Answer: 3.28 mins

Explanation:

Here’s how it breaks down:

Conversions

74 mph = 33.08 m/s

6.5 km = 6500 m

(6500 m)/(33.08 m/s) = 196.5 seconds

196.5 seconds is equivalent to 3.28 minutes

Explanation:

It is established that 1 gram is equivalent to 1000 milligrams. We can express this mathematically in the following way.

              or

Thus, to convert grams to milligrams, we simply multiply the number by 1000. Conversely, for converting milligrams back to grams, we divide by 1000.