Stock System naming for NaCl4, SO3, As2F4.

How many valence electrons are in atom of sulfur?

Nookie1986 [14]

The answer is six because it is in group six A on the periodic table.

8 0

2 years ago

An ideal gas contained in a piston-cylinder assembly is compressed isothermally in an internally reversible process.

Tju [1.3M]

Answer:

a) $\Delta S$

b) entropy of the sistem equal to a), entropy of the universe grater than a).

Explanation:

a) The change of entropy for a reversible process:

$\delta S=\frac{\delta Q}{T}$

$\Delta S=\frac{Q}{T}$

The energy balance:

$\delta U=[tex]\delta Q- \delta W$

If the process is isothermical the U doesn't change:

$0=[tex]\delta Q- \delta W$

$\delta Q= \delta W$

$Q= W$

The work:

$W=\int_{V1}^{V2}P*dV$

If it is an ideal gas:

$P=\frac{n*R*T}{V}$

$W=\int_{V1}^{V2}\frac{n*R*T}{V}*dV$

Solving:

$W=n*R*T*ln(V2/V1)$

Replacing:

$\Delta S=\frac{n*R*T*ln(V2/V1)}{T}$

$\Delta S=n*R*ln(V2/V1)}$

Given that it's a compression: V2<V1 and ln(V2/V1)<0. So:

$\Delta S$

b) The entropy change of the sistem will be equal to the calculated in a), but the change of entropy of the universe will be 0 in a) (reversible process) and in b) has to be positive given that it is an irreversible process.

7 0

3 years ago

A clear liquid in an open container is allowed to evaporate. After three days, a solid is left in the container. Was the clear

Mashutka [201]

The liquid did not chemically bond after 3 days, therefor it is a mixture.

Hope this helps!

7 0

2 years ago

During the experiment a student precipitated and digested the BaSO4. After allowing the precipitate to settle, they added a few

OlgaM077 [116]

Answer:

Incomplete precipitation of barium sulfate

Explanation:

The student has precipitated and digested the barium sulfate on his/her side. But on the addition of $BaCl_2$ in the solution, the solution become cloudy. This happened because incomplete precipitation of barium sulfate by the student. When $BaCl_2$ is added, there are still sulfate ions present in the solution with combines with $BaCl_2$ and forms $BaSO_4$ and the formation of this precipitate makes the solution cloudy.

7 0

3 years ago

Determine the formula of chromic acid.

Katyanochek1 [597]

<u>Answer:</u> The formula of chromic acid is $H_2CrO_4$

<u>Explanation:</u>

We are given an ionic compound named as chromic acid. This acid is formed by the combination of hydrogen ion and chromate ion.

An acid is defined as the substance which releases hydrogen ion when dissolved in water.

Hydrogen is the 1st element of periodic table having electronic configuration of $1s^1$ .

This element will loose 1 electron to form $H^{+}$ ion.

Chromate ion is a polyatomic ion having chemical formula of $CrO_4^{2-}$

By criss-cross method, the oxidation state of the ions gets exchanged and they form the subscripts of the other ions. This results in the formation of a neutral compound.

So, the chemical formula for the given compound is $H_2CrO_4$

Thus, the formula of chromic acid is $H_2CrO_4$

8 0

2 years ago