All categories

3 years ago

A solution is made by dissolving

Chemistry

1 answer:

Furkat [3]3 years ago

8 0

Answer:

2.29 m.

Explanation:

The following data were obtained from the question:

Mass of KOH = 42.3 g

Molar mass of KOH = 56.11 g/mol

Mass of water = 329 g

Molality of KOH = ?

Next, we shall determine the number of mole in 42.3 g of KOH. This can be obtained as follow:

Mass of KOH = 42.3 g

Molar mass of KOH = 56.11 g/mol

Mole of KOH =?

Mole = mass /Molar mass

Mole of KOH = 42.3/56.11

Mole of KOH = 0.754 mole

Next, we shall convert 329 g of water to kilogram (kg). This can be obtained as follow:

1000 g = 1 kg

Therefore,

329 g = 329 g /1000 g × 1 kg

329 g = 0.329 kg

Therefore, 329 g of water is equivalent to 0.329 kg

Finally, we shall determine the molality of the KOH solution ad follow:

Molality is defined as the mole of solute per unit kilogram of solvent (water) i.e

Molality = mole/ mass (kg) of water

Mole of KOH = 0.754 mole.

Mass of water = 0.329 kg.

Molality = mole/ mass (kg) of water

Molality = 0.754/0.329

Molality = 2.29 m

Therefore, the molality of the KOH solution is 2.29 m.

You might be interested in

What is the molar mass of a gas if 0.102 g of the gas occupies 0.070 L at STP? a. 32.6g / mol b. 28.2 g/mol c. 40.0g / mol d. 47

alexgriva [62]

Answer:

A. 32.6 g/mol

Explanation:

First convert the volume of gas to moles using the ratio 1 mol / 22.4 L at STP.

0.070 L • (1 mol / 22.4 L) = 0.00313 mol

Now divide the grams of gas by the moles of gas:

0.102 g / 0.00313 mol = 32.6 g/mol

8 0

2 years ago

For alpha decay to cause a loss in mass, such as that in the uranium 238 conversion to thorium 234, what must the atomic weight

Aleonysh [2.5K]

Explanation:

Reaction equation showing alpha decay in Uranium-238 is as follows.

$^{238}_{92}U \rightarrow ^{234}_{90}Th + ^{4}_{2}He$

It is known that an alpha particle is basically a helium nucleus and it contains 2 protons and 2 neutrons.

Symbol of an alpha particle is $^{4}_{2}\alpha$ .

As atomic mass or weight is the sum of total number of protons and neutrons present in an atom.

Hence, the atomic weight of the alpha particle is (2 + 2) = 4.

6 0

2 years ago

Determining nitrogen balance in the clinical setting can be very valuable. To determine a client’s state of nitrogen balance, a

nikdorinn [45]

Answer:

We also need the nitrogen intake

Explanation:

The nitrogen balance is the difference between the nitrogen intake and nitrogen excreted. If this calculation is positive, the body grow; if it is negative, the body is decreased.

6 0

2 years ago

What is the molarity of a NaCl stock used to make 750 ml of a dilute 10 mM solution if 5 ml of the concentrated solution was use

ch4aika [34]

Explanation:

The given data is as follows.

$M_{1}$ = 10 mM = $10 \times 10^{-3}$ M

$V_{1}$ = 750 ml, $V_{2}$ = 5 ml

$M_{2}$ = ?

Therefore, calculate the molarity of given NaCl stock as follows.

$M_{1} \times V_{1} = M_{2} \times V_{2}$

$10 \times 10^{-3} \times 750 ml = M_{2} \times 5 ml$

$M_{2}$ = 1.5 M

Thus, we can conclude that molarity of given NaCl stock is 1.5 M.

7 0

2 years ago

Answer the amount of miles of O2

lord [1]

Answer:

Explanation:

the answer is 3 because it is 3 for the o2 so 3 you have to pay more attention for the small ditails

5 0

2 years ago