All categories

2 years ago

How many moles are in a 111.5 gram sample of sodium chloride, NaCl?

Chemistry

1 answer:

Katarina [22]2 years ago

5 0

Answer: 1.91 moles

Explanation:

First you want to find the molar mass of NaCL

Na = 22.99g Cl = 35.45g

22.99g + 35.45g = 54.44g

Then divide 111.5g by 54.44g and this will give you moles.

You might be interested in

If is found that 24.68 mL of .1165 M NaOH is needed to titrate .2931 g of an unknown acid to the phenolphthalein end point. Calc

Lemur [1.5K]

Answer: The equivalent mass of the acid is 83.16 grams

Explanation:

To calculate the number of moles for given molarity, we use the equation:

$\text{Moles of solute}={\text{Molarity of the solution}}\times{\text{Volume of solution (in L)}}$

Molarity of $NaOH$ solution = 0.1165 M

Volume of $NaOH$ solution = 24.68 mL = 0.02468 L

Putting values in equation 1, we get:

$\text{Moles of} NaOH={0.1165M}\times{0.02468L}=2.875\times 10^{-3}moles=2.875\times 10^{-3}geq$

( as acidity of NaOH is 1)

For end point: gram equivalents of acid = gram equivalents of base = $2.875\times 10^{-3}$

Mass of acid= $gram equivalents\times {\text {Equivalent mass}}$

$0.2391=2.875\times 10^{-3}\times {\text {Equivalent mass}}$

${\text {Equivalent mass}}=83.16g$

Thus equivalent mass of the acid is 83.16 grams

5 0

3 years ago

You need to prepare 100.0 mL of a pH 4.00 buffer solution using 0.100 M benzoic acid (p K a = 4.20 ) and 0.200 M sodium benzoate

bekas [8.4K]

Answer : The volume of sodium benzoate and benzoic acid solution mixed to prepare this buffer should be, 29.0 mL and 71 mL respectively.

Explanation :

Let the volume of sodium benzoate (salt) be, x

So, the volume of benzoic acid (acid) will be, (100 - x)

Using Henderson Hesselbach equation :

$pH=pK_a+\log \frac{[Salt]}{[Acid]}$

Now put all the given values in this expression, we get:

$4.00=4.20+\log \left(\frac{(\frac{0.200x}{100})}{(\frac{0.100(100-x)}{100})}\right)$

x = 29.0

The volume of sodium benzoate = x = 29.0 mL

The volume of benzoic acid (acid) = (100 - x) = (100 - 29.0) = 71 mL

Thus, the volume of sodium benzoate and benzoic acid solution mixed to prepare this buffer should be, 29.0 mL and 71 mL respectively.

5 0

3 years ago

IceJOKER [234]

Answer: III and IV

Pls mark me as brainiest

7 0

2 years ago

mixtures, solubility, and Acid/Base Solutions lesson outline lesson 2 properties of solutions answer key

salantis [7]

In chemistry, mixtures, solubility, acid/base and solutions are all important to understanding volumetric analysis and chemical reactions.

<h3>What is a mixture?</h3>

A mixture is a any substance which consists of two or more constituents which are physically combined together.

Example of a mixture is bronze.

<h3>What is solubility?</h3>

Solubility of a solute in a given solvent is defined as the amount of solute that can be dissolved in that solvent at a particular temperature.

<h3>What are acids and bases?</h3>

An acid is a substance which produces hydrogen ions or protons as the only positive ions when dissolved in water.

Example of an acid is hydrochloric acid.

A base is a substance which reacts with an acid to produce salt and water only, thereby neutralizing the acid.

Example of a base is potassium hydroxide.

<h3>What are solutions?</h3>

Solutions are homogenous mixtures of a solute dissolved in a solvent.

Example of solutions are sugar solutions and saline water.

Therefore, mixtures, solubility, acid/base and solutions are all important to understanding volumetric analysis and reactions in chemistry.

Learn more about mixtures, solubility, acid/bases and solutions at: brainly.com/question/7314699

8 0

2 years ago

Which substance is likely to be the best conductor of electricity

Law Incorporation [45]

Any type of metal would be a good conductor of electricity.

8 0

3 years ago