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3 years ago

3. Find the mass of 4.77 x 1022 atoms of scandium (Sc).

Chemistry

1 answer:

iren2701 [21]3 years ago

7 0

Answer:

Mass = 3.6 g

Explanation:

Given data:

Number of atoms of scandium = 4.77×10²² atoms

Mass of arsenic = ?

Solution:

The given problem will solve by using Avogadro number.

It is the number of atoms , ions and molecules in one gram atom of element, one gram molecules of compound and one gram ions of a substance.

The number 6.022× 10²³ is called Avogadro number.

one mole = 6.02×10²³ atoms

one mole × 4.77×10²² atoms / 6.02×10²³ atoms

0.08 mol

Mass of scandium

Mass = number of moles × molar mass

Mass = 0.08 mol × 45 g/mol

Mass = 3.6 g

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9. Given the following reaction:CO (g) + 2 H2(g) CH3OH (g)In an experiment, 0.45 mol of CO and 0.57 mol of H2 were placed in a 1

WITCHER [35]

Answer:

$Keq=11.5$

Explanation:

Hello,

In this case, for the given reaction at equilibrium:

$CO (g) + 2 H_2(g) \rightleftharpoons CH_3OH (g)$

We can write the law of mass action as:

$Keq=\frac{[CH_3OH]}{[CO][H_2]^2}$

That in terms of the change $x$ due to the reaction extent we can write:

$Keq=\frac{x}{([CO]_0-x)([H_2]_0-2x)^2}$

Nevertheless, for the carbon monoxide, we can directly compute $x$ as shown below:

$[CO]_0=\frac{0.45mol}{1.00L}=0.45M\\$

$[H_2]_0=\frac{0.57mol}{1.00L}=0.57M\\$

$[CO]_{eq}=\frac{0.28mol}{1.00L}=0.28M\\$

$x=[CO]_0-[CO]_{eq}=0.45M-0.28M=0.17M$

Finally, we can compute the equilibrium constant:

$Keq=\frac{0.17M}{(0.45M-0.17M)(0.57M-2*0.17M)^2}\\\\Keq=11.5$

Best regards.

3 0

3 years ago

What is the change of e-

Afina-wow [57]

E- is a negative electron

6 0

3 years ago

In which situation would hydrogen bonding be present?

sineoko [7]

Answer:

Water ?

Need more info.

Water is $H_{2}$ <em>O</em>

Explanation:

6 0

3 years ago

Read 2 more answers

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Marrrta [24]

Answer: A. 1.60 liters

Explanation:

$2Na_2O_2+2CO_2\rightarrow 2Na_2CO_3+O_2$

As can be seen from the balanced chemical equation, 2 moles of $CO_2$ produce 1 mole of $O_2$ .

According to Avogadro's law, every 1 mole of the gas occupies 22.4 liters at STP.

Thus $2$ moles of $CO_2$ occupies $22.4\times 2=44.8L$ at STP and produce 1 mole of $O_2$ i.e. 22.4 L

44.8 L of $CO_2$ will produce 22.4 L of $O_2$

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3 years ago

Which statement is true about air temperature and humidity

lapo4ka [179]

Complete Question:

Which statement is true about air temperature and humidity?

Group of answer choices.

a. the air temperature does not affect how much moisture the air can hold

b. hotter air holds less moisture than colder air.

c. hot air and cold air share the same amount of moist.

d. colder air holds less moisture than hotter air.

Answer:

d. colder air holds less moisture than hotter air

Explanation:

Weather can be defined as the atmospheric conditions of a particular area over a short period of time.

The elements of weather include precipitation, wind, temperature, atmospheric pressure, relative humidity, cloud, and wind speed.

Temperature can be defined as a measure of the degree of coldness or hotness of a physical object (body).

On the other hand, humidity refers to the concentration (amount) of water vapor that is present in the air. It is high when there's a lot of water vapor in the air and low when the level of water vapor is small.

Hence, the true statement about air temperature and humidity is that colder air holds less moisture than hotter air because as the air cools, its molecules move closer together while the molecules move farther apart as the air become hot.

Additionally, at constant humidity, relative humidity is inversely proportional to temperature i.e as the temperature decreases, relative humidity increases.

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3 years ago