Location of nucleus in skeletal smooth and cardiac

How many grams of NaCl (MM = 58.44g/mol) are in 250mL of a 0.75 molar solution?

Artist 52 [7]

Answer:

$\boxed {\boxed {\sf 11 \ grams \ NaCl}}$

Explanation:

We are asked to find how many grams of sodium chloride are in a solution.

<h3>1. Moles of Solute </h3>

Molarity is a measure of concentration in moles per liter.

$molarity= \frac{ moles \ of \ solute}{liters \ of \ solution}$

We know the molarity is 0.75 molar. 1 molar is the same as 1 mole per liter, so the solution contains 0.75 moles of sodium chloride per liter.

There are 250 milliliters of solution but molarity uses liters for volume. We must convert milliliters to liters. Remember that 1 liter contains 1000 milliliters. Set up a ratio and use dimensional analysis to convert.

$250 \ mL * \frac{1 \ L} {1000\ mL} = \frac{ 250}{1000} \ L = 0.250 \ L$

Now we know the molarity and the liters of solution, but the moles of solute are unknown.

molarity = 0.75 mol NaCl/L
moles of solute =x
liters of solution = 0.25 L

Substitute the values into the formula.

$0.75 \ mol \ NaCl/L = \frac{x}{0.250 \ L}$

We are solving for the moles of solute, so we must isolate the variable x. It is being divided by 0.250 liters. The inverse of division is multiplication, so multiply both sides of the equation by 0.250 L.

$0.250 \ L *0.75 \ mol \ NaCl/L = \frac{x}{0.250 \ L} * 0.250 \ L$

$0.250 \ L *0.75 \ mol \ NaCl/L = x$

The units of liters cancel.

$0.250 * 0.75 \ mol \ NaCl$

$\bold {0.1875 \ mol \ NaCl}$

<h3>2. Grams of Solute </h3>

Now that we have calculated the moles of solute, we must convert this to grams. We use the molar mass or the mass of 1 mole of a substance. Sodium chloride's molar mass is given and it is 58.44 grams per mole. This means there are 58.44 grams of sodium chloride in 1 mole of sodium chloride.

Set up a ratio so we can convert using dimensional analysis.

$\frac {58.44 \ g \ NaCl}{1 \ mol \ NaCl}$

Multiply by the number of moles we calculated.

$0.1875 \ mol \ NaCl *\frac {58.44 \ g \ NaCl}{1 \ mol \ NaCl}$

The units of moles of sodium chloride cancel.

$0.1875 *\frac {58.44 \ g \ NaCl}{1}$

$\bold {10.9575 \ g \ NaCl}$

<h3>3. Round using Significant Figures </h3>

The original measurements of molarity and volume have 2 significant figures, so our answer must have the same. For the number we calculated, that is the ones place. The 9 in the tenths place tells us to round the 0 up to a 1.

$11 \ g \ NaCl$

<u>There are approximately </u><u>11 grams of sodium chloride</u><u> in 250 mL of a 0.75 molar solution.</u>

8 0

3 years ago

What does the Bohr Model show us?

Mumz [18]

Answer:

the number of electrons

3 0

3 years ago

Read 2 more answers

What are the numbers of orbitals in sublevel of s?

MaRussiya [10]

1 orbital in that sub level I think

6 0

4 years ago

The textbook procedure is asking you to dissolve 1 g of 3-nitrophthalic acid in hydrazine and only then to add the triethylene g

Ivenika [448]

Answer:

The reaction between 3-nitrophthalic acid and hydrazine is highly vigorous. Therefore, the answer is <em>option C</em>.

Explanation:

Triethylene glycol is a high-boiling solvent which necessarily used to contain the synthesis of luminol, which is obtained from the reaction between 3-nitrophthalic acid and aqueous hydrazine. However, this reaction is carried out at a very high temperature, the prior addition of triethylene glycol can allow sufficient reflux for the required completion time without evaporating the solvent fully.

Furthermore, Luminol is an organic compound used to detect metallic ions in Biology. For example, it is used to detect blood traces in forensic investigations.

7 0

3 years ago

HELP ASAP!! DON'T COPY FROM G00GLE

allsm [11]

Parts of respiratory system:

Nose and Nasal Cavity, mouth, Pharynx, Larynx, Trachea, Bronchi and Bronchioles, Lungs and Muscles of Respiration.

Respiratory system function:

Your respiratory system is the network of organs and tissues that help you breathe. This system helps your body absorb oxygen from the air so your organs can work. It also cleans waste gases, such as carbon dioxide, from your blood.

Alveoli:

Alveoli are tiny sacs of air in your lungs that take up the oxygen you breathe and keep it going. The alveoli ventilate, diffuse and peruse in your lungs.

3 0

3 years ago