All categories

3 years ago

How much water is needed to prepare a .50 molal solution using 0.50 moles of sodium chloride??

1 answer:

4 0

Answer:1kg. Explanation: ( b is the symbol for molality, and molality is the number of moles of solute per kilogram of solvent). b=nm. 0.5=0.5m. m=1kg.

Explanation:

You might be interested in

For each of the following ionic bonding examples, show the transfer of electrons, the ions resulting with the charges and the fi

fgiga [73]

Answer:

BaO

Ba gives up two electrons and becomes Ba⁺²
O takes two electron and becomes O⁻²

Al₂O₃

Mg₃P₂

Na₂O

CaCl₂

6 0

3 years ago

Can someone help me with questions 4-5 <br> 21 points

sp2606 [1]

4. describe three ways carbon dioxide was removed from the Earth's atmosphere.

Answer: Forests: Photosynthisis helps clear carbon dioxide naturally, Soils naturally store carbon, but agricultural soils are running a big deficit due to intensive use. Because agricultural land is so expansive, Bio-energy with Carbon Capture and Storage (BECCS) is another way to use photosynthesis to combat climate change. However, it is far more complicated than planting trees or managing soils — and it doesn’t always work for the climate.

5. Explain why there is now 21% Oxygen in the Earth's atomosphere compaired to little or no Oxygen in the Earth's atmosphere 4.5 billion years ago.

Answer: cientists believe that the Earth was formed about 4.5 billion years ago. Its early atmosphere was probably formed from the gases given out by volcanoes. It is believed that there was intense volcanic activity for the first billion years of the Earth's existence.The early atmosphere was probably mostly carbon dioxide, with little or no oxygen. There were smaller proportions of water vapour, ammonia and methane. As the Earth cooled down, most of the water vapour condensed and formed the oceans.

Sorry its soooo long TwT

8 0

3 years ago

How many grams of chlorine gas can be produced when 50.0 grams of aluminum chloride decompose? 2AlCl3→ 2Al + 3Cl2

lianna [129]

Answer:

Explanation:

Approx.

425

⋅

Explanation:

(

)

(

)

→

(

)

You have given a stoichiometrically balanced equation, so bravo.

The equation explicitly tells us that

⋅

of aluminum metal reacts with

35.45

⋅

gas to give

266.7

⋅

aluminum trichloride

hope this helps

6 0

3 years ago

What is abbreviated structural formula of the 2-metil-5-isopropiloctan?

Alja [10]

Answer:

CH3

CH3- C H -CH2-CH2- CH - CH2-CH2-CH3

/ \

CH3 CH3

Explanation:

Octan

C-C-C-C-C-C-C-C

Metyl

CH3 -

Isopropyl

CH3

- CH

CH3

2-metil-5-isopropiloctan

CH3

CH3- C H -CH2-CH2- CH - CH2-CH2-CH3

/ \

CH3 CH3

8 0

3 years ago

What is the freezing point of a solution of 498mL of water (solute) dissolved in 2.50 L of ethanol (solvent), C2H5OH? The densit

jok3333 [9.3K]

Answer:

Freezing T° of solution is -142.4°C

Explanation:

This excersise is about colligative properties, in this case freezing point depression,

ΔT = Kf . m . i

Where ΔT = Freezing T° of solvent - Freezing T° of solution

Kf = Cryoscopic constant

m = mol/kg (molality)

i = Number of ions dissolved.

Water is not ionic, so i = 1

Let's find out m.

We determine mass of water, by density

498ml . 1 g/mL = 498 g

We convert the mass of water to moles → 498 g . 1mol/18g = 27.6 moles

We determine mass of solvent by density

2500 mL . 0.789 g/mL = 1972.5 g

Notice, we had to convert L to mL to cancel units.

1 cm³ = 1 mL

We convert the mass from g to kg → 1972.5 g . 1kg /1000g = 1.97kg

We determine m = mol/kg → 27.6mol / 1.97kg = 13.9 m

Kf for ethanol is: 1.99 °C/m

Freezing T° for ethanol is: -114.6°C

We replace at formula: - 114.6°C - Freezing T° solution = 1.99 °C/m . 13.9 m . 1

- 114.6°C - Freezing T° solution = 27.8 °C

- Freezing T° solution = 27.8°C + 114.6°C

Freezing T° Solution = - 142.4 °C

7 0

3 years ago