Understanding chemistry and its principles enables us to predict and understand various properties of substances. For example, because we know that ionic bonds are very strong and difficult to break, we know that any substance that has these bonds will have a high melting point, because melting is a process that requires the intermolecular bonds present in the solid state to be broken. This can be applied to table salt, sodium chloride, which has an ionic structure and a melting point of almost 800 degrees Celsius. Similarly, many other properties and characteristics may be predicted using concepts of chemistry.

8 0

3 years ago

A) The average molecular speed in a sample of Ar gas at a certain temperature is 391 m/s. The average molecular speed in a sampl

diamong [38]

Answer:

For A: The average molecular speed of Ne gas is 553 m/s at the same temperature.

For B: The rate of effusion of $SO_2$ gas is $1.006\times 10^{-3}mol/hr$

Explanation:

For A:

The average molecular speed of the gas is calculated by using the formula:

$V_{gas}=\sqrt{\frac{8RT}{\pi M}}$

$V_{gas}\propto \sqrt{\frac{1}{M}}$

where, M is the molar mass of gas

Forming an equation for the two gases:

$\frac{V_{Ar}}{V_{Ne}}=\sqrt{\frac{M_{Ne}}{M_{Ar}}}$ .....(1)

Given values:

$V_{Ar}=391m/s\\M_{Ar}=40g/mol\\M_{Ne}=20g/mol$

Plugging values in equation 1:

$\frac{391m/s}{V_{Ne}}=\sqrt{\frac{20}{40}}\\\\V_{Ne}=391\times \sqrt{2}=553m/s$

Hence, the average molecular speed of Ne gas is 553 m/s at the same temperature.

For B:

Graham's law states that the rate of diffusion of a gas is inversely proportional to the square root of the molar mass of the gas. The equation for this follows:

$Rate\propto \frac{1}{\sqrt{M}}$

Where, M is the molar mass of the gas

Forming an equation for the two gases:

$\frac{Rate_{SO_2}}{Rate_{Xe}}=\sqrt{\frac{M_{Xe}}{M_{SO_2}}}$ .....(2)

Given values:

$Rate_{Xe}=7.03\times 10^{-4}mol/hr\\M_{Xe}=131g/mol\\M_{SO_2}=64g/mol$

Plugging values in equation 2:

$\frac{Rate_{SO_2}}{7.03\times 10^{-4}}=\sqrt{\frac{131}{64}}\\\\Rate_{SO_2}=7.03\times 10^{-4}\times \sqrt{\frac{131}{64}}\\\\Rate_{SO_2}=1.006\times 10^{-3}mol/hr$

Hence, the rate of effusion of $SO_2$ gas is $1.006\times 10^{-3}mol/hr$

8 0

2 years ago

How many hydrogen atoms are present in a hydrocarbon chain of five carbons joined to each other by single covalent bonds?

zhenek [66]

Answer:

12 hydrogen atoms are present.

Explanation:

The hydrocarbon is an alkane as it contains single covalent bonds.

The first carbon attaches to 3 hydrogen atoms, the second to fourth carbon attaches to 2 hydrogen atoms each and the last (fifth) carbon have 3 hydrogen atoms.

The Alkane compound is called PENTANE with molecular formula C5H12.

5 0

2 years ago