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3 years ago

three of the following are base units used in the metric system. which is not a base unit? meter liter kilogram gram

1 answer:

8 0

The base units used in the metric system are meter for the measurement of distance or displacement, liter as unit measurement of volume, kilogram as a unit of measurement of mass and seconds as unit of measurement of time. The answer is here is D. gram.

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Argon (Ar) and helium (He) are initially in separate compartments of a container at 25°C. The

love history [14]

Answer:

(a) $V_B=11.68L$

(b) $x_{He}=0.533$

Explanation:

Hello,

In this case, since the both gases behave ideally, with the given information we can compute the moles of He in A:

$n_A=\frac{0.082\frac{atm*L}{mol*K}*298K}{1.974 atm*6.00L}=2.063mol$

Thus, since the final pressure is 3.60 bar, we can write:

$P=x_{Ar}P_A+x_{He}P_B\\\\P=\frac{n_{Ar}}{n_{Ar}+n_{He}} P_A+\frac{n_{He}}{n_{Ar}+n_{He}} P_B\\\\3.60bar=\frac{2.063mol}{2.063mol+n_{He}} *2.00bar+\frac{n_{He}}{2.063mol+n_{He}} *5.00bar$

The moles of helium could be computed via solver as:

$n_{He}=2.358mol$

Or algebraically:

$3.60bar=\frac{1}{2.063mol+n_{He}} *(4.0126+5.00*n_{He})\\\\7.314+3.60n_{He}=4.013+5.00*n_{He}\\\\7.314-4.013=5.00*n_{He}-3.60n_{He}\\\\n_{He}=\frac{3.3}{1.4}=2.358mol$

In such a way, the volume of the compartment B is:

$V_B=\frac{n_{He}RT}{P_B}=\frac{2.358mol*0.082\frac{atm*L}{mol*K}*298.15K}{4.935atm}\\ \\V_B=11.68L$

Finally, he mole fraction of He is:

$x_{He}=\frac{2.358}{2.358+2.063}\\ \\x_{He}=0.533$

Regards.

8 0

3 years ago

H2(g) + Co(g) _CH3OH<br> balance the equation <br>

Tom [10]

Answer:

CO + 2H2 = CH3OH

Explanation:

1. Label Each Compound With a Variable

aCO + bH2 = cCH3OH

2. Create a System of Equations, One Per Element

C: 1a + 0b = 1c

O: 1a + 0b = 1c

H: 0a + 2b = 4c

3. Solve For All Variables (using substitution, gauss elimination, or a calculator)

a = 1

b = 2

c = 1

4. Substitute Coefficients and Verify Result

CO + 2H2 = CH3OH

L R

C: 1 1 ✔️

O: 1 1 ✔️

H: 4 4 ✔️

8 0

2 years ago

What causes the sugar to dissolve in water?

vaieri [72.5K]

Answer:

Sugar dissolves in water because energy is given off when the slighty polar sucrose molecules form intermoleeular bonds with the polar water molecules.

Explanation:

3 0

3 years ago

Read 2 more answers

1‑Propanol ( P⁰ 1 = 20.9 Torr at 25 ⁰C ) and 2‑propanol ( P⁰ 2 = 45.2 Torr at 25 ⁰C ) form ideal solutions in all proportions. L

anastassius [24]

Answer : The mole fraction of vapor phase 1‑Propanol and 2‑Propanol is, 0.352 and 0.648 respectively.

Explanation : Given,

Vapor presume of 1‑Propanol $(P^o_1)$ = 20.9 torr

Vapor presume of 2‑Propanol $(P^o_2)$ = 45.2 torr

Mole fraction of 1‑Propanol $(x_1)$ = 0.540

Mole fraction of 2‑Propanol $(x_2)$ = 1-0.540 = 0.46

First we have to calculate the partial pressure of 1‑Propanol and 2‑Propanol.

$p_1=x_1\times p^o_1$

where,

$p_1$ = partial vapor pressure of 1‑Propanol

$p^o_1$ = vapor pressure of pure substance 1‑Propanol

$x_1$ = mole fraction of 1‑Propanol

$p_1=(0.540)\times (20.9torr)=11.3torr$

and,

$p_2=x_2\times p^o_2$

where,

$p_2$ = partial vapor pressure of 2‑Propanol

$p^o_2$ = vapor pressure of pure substance 2‑Propanol

$x_2$ = mole fraction of 2‑Propanol

$p_2=(0.46)\times (45.2torr)=20.8torr$

Thus, total pressure = 11.3 + 20.8 = 32.1 torr

Now we have to calculate the mole fraction of vapor phase 1‑Propanol and 2‑Propanol.

$\text{Mole fraction of 1-Propanol}=\frac{\text{Partial pressure of 1-Propanol}}{\text{Total pressure}}=\frac{11.3}{32.1}=0.352$

and,

$\text{Mole fraction of 2-Propanol}=\frac{\text{Partial pressure of 2-Propanol}}{\text{Total pressure}}=\frac{20.8}{32.1}=0.648$

Thus, the mole fraction of vapor phase 1‑Propanol and 2‑Propanol is, 0.352 and 0.648 respectively.

3 0

3 years ago

calcium has atomic number of 20 how many electrons of a calcium atom are involved in chemical bonding

Lelu [443]

The answer is 2 electrons.

The electron configuration of calcium is 2:8:8:2

Calcium has two electrons in its outermost shell. These are its valence electrons and are the ones used in bonding with other elements. Valence electrons of an atom are those electrons that are in its outer energy shell or that are available for bonding.

Calcium is a metal. When metals react with non-metals, electrons are transferred from the metal atoms to the non-metal atoms forming ions. The resulting compound is known as an ionic compound.

For example, when calcium metal reacts with chlorine gas, calcium gives up its two valence electrons and Chlorine accepts them resulting in a new substance called calcium chloride in which the two elements have ended up forming ionic bonds.

7 0

4 years ago

Read 2 more answers