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3 years ago

Pure substance definition in chemistry?

1 answer:

3 0

A pure substance is a sample of matter with both definite and constant composition with distinct chemical properties. To avoid confusion, in chemistry a pure substance is often referred to as a "chemical substance".

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Please help, need answer

defon

I would say the first three. But I'm not 100% sure. I'm truly sorry if it's wrong

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3 years ago

When iron reacts with moist air to form rust, an ionic compound results because

UNO [17]

I am pretty sure it is d if i am wrong please tell me

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3 years ago

The structure of the Earth is divided into four major components: the crust, the mantle, the outer core, and the inner core.

SSSSS [86.1K]

It is true, they are the 4 main layers.

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3 years ago

During the discussion of gaseous diffusion for enriching uranium, it was claimed that 235UF6 diffuses 0.4% faster than 238UF6. S

Kay [80]

Answer: The below calculations proves that the rate of diffusion of $^{235}UF_6$ is 0.4 % faster than the rate of diffusion of $^{238}UF_6$

Explanation:

To calculate the rate of diffusion of gas, we use Graham's Law.

This law states that the rate of effusion or diffusion of gas is inversely proportional to the square root of the molar mass of the gas. The equation given by this law follows the equation:

$\text{Rate of diffusion}\propto \frac{1}{\sqrt{\text{Molar mass of the gas}}}$

We are given:

Molar mass of $^{235}UF_6=349.034348g/mol$

Molar mass of $^{238}UF_6=352.041206g/mol$

By taking their ratio, we get:

$\frac{Rate_{(^{235}UF_6)}}{Rate_{(^{238}UF_6)}}=\sqrt{\frac{M_{(^{238}UF_6)}}{M_{(^{235}UF_6)}}}$

$\frac{Rate_{(^{235}UF_6)}}{Rate_{(^{238}UF_6)}}=\sqrt{\frac{352.041206}{349.034348}}\\\\\frac{Rate_{(^{235}UF_6)}}{Rate_{(^{238}UF_6)}}=\frac{1.00429816}{1}$

From the above relation, it is clear that rate of effusion of $^{235}UF_6$ is faster than $^{238}UF_6$

Difference in the rate of both the gases, $Rate_{(^{235}UF_6)}-Rate_{(^{238}UF_6)}=1.00429816-1=0.00429816$

To calculate the percentage increase in the rate, we use the equation:

$\%\text{ increase}=\frac{\Delta R}{Rate_{(^{235}UF_6)}}\times 100$

Putting values in above equation, we get:

$\%\text{ increase}=\frac{0.00429816}{1.00429816}\times 100\\\\\%\text{ increase}=0.4\%$

The above calculations proves that the rate of diffusion of $^{235}UF_6$ is 0.4 % faster than the rate of diffusion of $^{238}UF_6$

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3 years ago

How do stomata help a plant maintain balance with their environment?

AnnZ [28]

Stomatal pores in plants regulate the amount of water and solutes within them by opening and closing their guard cells using osmotic pressure. In order for plants to produce energy and maintain cellular function, their cells undergo the highly intricate process of photosynthesis .

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3 years ago