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4 years ago

A solution is prepared by condensing 4.00 L of a gas,

Chemistry

1 answer:

vredina [299]4 years ago

5 0

Answer:

-2.3 ºC

Explanation:

Kf (benzene) = 5.12 ° C kg mol – 1

1st - We calculate the moles of condensed gas using the ideal gas equation:

n = PV / (RT)

P = 748/760 = 0.984 atm

T = 270 + 273.15 = 543.15 K

V = 4 L

R = 0.082 atm.L / mol.K

n = (0.984atm * 4L) / (0.082atm.L / K.mol * 543.15K) = 0.088 mol

Then, you calculate the molality of the solution:

m = n / kg solvent

m = 0.088 mol / 0.058 kg = 1.52mol / kg

Then you calculate the decrease in freezing point (DT)

DT = m * Kf

DT = 1.52 * 5.12 = 7.8 ° C

Knowing that the freezing point of pure benzene is 5.5 ºC, we calculate the freezing point of the solution:

T = 5.5 - 7.8 = -2.3 ºC

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The volume of 1.20 lol of gas at 61.3 kPa and 25.0 degree Celsius is

aniked [119]

Answer:

V = 48.5 L

Explanation:

Converting °C to K and kPa to atm

T = 25.0°C + 273.15 = 298.15 K

P = 61.3 kPa × (1 atm / 101.325 kPa) = 0.60498 atm

Calculating the volume of gas

V = nRT / P

V = (1.20 mol)(0.082057 L•atm/mol•K)(298.15 K) / 0.60498 atm

V = 48.5 L

4 0

3 years ago

Cho 4g CuO vào dung dịch axit clohidric 10% thì phản ứng vừa đủ.

Sholpan [36]

Answer:

Explanation:

a. CuO+ 2HCl⇒CuCl2+ H2O

b. $n_{CuO}$ = $\frac{4}{80}$ = 0,05 (mol)

⇒ $n_{CuCl2}$ = $n_{CuO}$ =0,05 mol

⇒ $m_{CuCl2}$ = 0,05×135=6,75 (g)

c. $n_{HCl}$ =2× $n_{CuO}$ =0,1 (mol)

⇒ $m_{HCl}$ = 0,1×36,5= 3,65 (g)

⇒ $m_{dd HCl}$ = $\frac{m_{HCl}}{10}$ ×100=36,5 (g)

⇒ Nồng độ phần trăm dd sau phản ứng= Nồng độ % dd CuCl2= $\frac{m_{CuCl2} }{m_{dd HCl+ m_{CuO} } }$ ×100= $\frac{6,75}{36,5+4}$ ×100≈ 16,67%

8 0

3 years ago

Define unit hi hope u have a great day

Crank

Answer:

Unit is the quantity of a constant magnitude which is used to measure the magnitudes of other quantities of the same nature. 

Explanation:

6 0

3 years ago

How do acids preserve food

tatyana61 [14]

Explanation:

acids reduce the pH of the food.if used properly,the pH will be reduced to a range where pathogens and many spoilage organisms will not grow

4 0

3 years ago

Read 2 more answers

What statement is incorrect about this oxidation-reduction reaction? 2 SO2(g) + O2(g) → 2 SO3(g) What statement is incorrect abo

Leno4ka [110]

Answer:

The incorrect statement is: SO₂ gains electrons

Explanation:

A chemical reaction that involves the simultaneous transfer of electrons between two chemical species, is known as the redox reaction.

Given chemical reaction: 2SO₂(g) + O₂(g) → 2SO₃(g)

In this redox reaction, S is present in +4 oxidation state in SO₂ and +6 oxidation state SO₃. Whereas, O is present in 0 oxidation state in O₂ and -2 oxidation state in SO₃.

Therefore, SO₂ loses electrons and thus gets oxidized. Whereas, O₂ gains electrons and thus gets reduced.

In this reaction, SO₂ is the reducing agent and O₂ is the oxidizing agent.

6 0

3 years ago