If the solvent is a liquid, then the solute:

Carbon dioxide is a compound of the elements carbon and oxygen (CO2). What happened to the carbon and oxygen to create this comp

dexar [7]

Answer:

D. they exchanged electrons

6 0

2 years ago

The half-life of a strontium isotope is 25 years. How much of this particular isotope will remain after 100 years if the startin

Phoenix [80]

Answer:

1 gram

Explanation:

Half life = 25 years

Starting mass = 16 grams

Time = 100 years

Number of half lives = Time / Duration of Half life = 100 / 25 = 4

After first Half life;

Remaining mass = 16 / 2 = 8 g

After Second Half life;

Remaining mass = 8 / 2 = 4 g

After Third Half life;

Remaining mass = 4 / 2 = 2 g

After Fourth Half life;

Remaining mass = 2 / 2 = 1 g

3 0

2 years ago

After undergoing alpha decay, an atom of radium-226 becomes

Zanzabum

The answer is b. radon-222. The alpha decay means that it will emit an alpha particle when decays. The alpha particle has two protons and two neutrons. So Radium(88) minus two protons will become Radon(86). And the atomic mass will become 226-4=222.

8 0

2 years ago

Compare and contrast the processes of mining coal and extracting oil

Yuki888 [10]

Answer:

When you mine, you usually drill the oil whereas you mechanically press oil when you extract it.

Explanation:

hope this helped, sry it took so long.

4 0

3 years ago

a) Whatis the composition in mole fractions of a solution of benzene and toluene that has a vapor pressure of 35 torr at 20 °C?

iogann1982 [59]

Answer:

molar composition for liquid

xb= 0.24

xt=0.76

molar composition for vapor

yb=0.51

yt=0.49

Explanation:

For an ideal solution we can use the Raoult law.

Raoult law: in an ideal liquid solution, the vapor pressure for every component in the solution (partial pressure) is equal to the vapor pressure of every pure component multiple by its molar fraction.

For toluene and benzene would be:

$P_{B}=x_{B}*P_{B}^{o}$

$P_{T}=x_{T}*P_{T}^{o}$

Where:

$P_{B}$ is partial pressure for benzene in the liquid

$x_{B}$ is benzene molar fraction in the liquid

$P_{B}^{o}$ vapor pressure for pure benzene.

The total pressure in the solution is:

$P= P_{T}+ P_{B}$

And

$1=x_{B}+x_{T}$

Working on the equation for total pressure we have:

$P=x_{B}*P_{B}^{o} + x_{T}*P_{T}^{o}$

Since $x_{T}=1-x_{B}$

$P=x_{B}*P_{B}^{o} + (1-x_{B})*P_{T}^{o}$

We know P and both vapor pressures so we can clear $x_{B}$ from the equation.

$x_{B}=\frac{P- P_{T}^{o}}{ P_{B}^{o} - P_{T}^{o}}$

$x_{B}=\frac{35- 22}{75-22} = 0.24$

So

$x_{T}=1-0.24 = 0.76$

To get the mole fraction for the vapor we know that in the equilibrium:

$P_{B}=y_{B}*P$

$y_{T}=1-y_{B}$

So

$y_{B} =\frac{P_{B}}{P}=\frac{ x_{B}*P_{B}^{o}}{P}$

$y_{B}=\frac{0.24*75}{35}=0.51$

$y_{T}=1-0.51=0.49$

Something that we can see in these compositions is that the liquid is richer in the less volatile compound (toluene) and the vapor in the more volatile compound (benzene). If we take away this vapor from the solution, the solution is going to reach a new state of equilibrium, where more vapor will be produced. This vapor will have a higher molar fraction of the more volatile compound. If we do this a lot of times, we can get a vapor that is almost pure in the more volatile compound. This is principle used in the fractional distillation.

7 0

3 years ago