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3 years ago

What occurs when a 35-gram aluminum cube at 100.°C is placed in 90. grams of water at 25°C in an insulated cup?

1 answer:

8 0

Heat always flows from hot to cold. The aluminum is hotter than the water in the cup so the answer is 2: The heat is transferred from the aluminum to the water, and the temperature of the water increases.

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PLEASE HELP! 25 POINTS!!!! I got the #1, just not #2 and #3. An industrial chemical company has opened a new plant that will pro

podryga [215]

Answer :

Part 1 : Balanced reaction, $3H_2(g)+N_2(g)\rightarrow 2NH_3(g)$

Part 2 : The theoretical yield of $NH_3$ gas = 440.96 g

Part 3 : The % yield of ammonia is 90.03 %

Solution : Given,

Mass of $N_2$ = 475 g

Molar mass of $N_2$ = 28 g/mole

Molar mass of $NH_3$ = 17 g/mole

Experimental yield of $NH_3$ = 397 g

Answer for Part (1) :

The balanced chemical reaction is,

$3H_2(g)+N_2(g)\rightarrow 2NH_3(g)$

Answer for Part (2) :

First we have to calculate the moles of $N_2$ .

$\text{Moles of }N_2=\frac{\text{ Mass of }N_2}{\text{ Molecular mass of }N_2}=\frac{475g}{28g/mole}=16.96moles$

From the given reaction, we conclude that

1 moles of $N_2$ gas react to give 2 moles of $NH_3$ gas

16.96 moles of $N_2$ gas react to give $\frac{2}{1}\times 16.96=33.92$ moles of $NH_3$ gas

Now we have to calculate the mass of $NH_3$ gas.

$\text{ Mass of }NH_3=\text{ Moles of }NH_3\times \text{ Molar mass of }NH_3$

$\text{ Mass of }NH_3=(33.92moles)\times (17g/mole)=440.96g$

Therefore, the theoretical yield of $NH_3$ gas = 440.96 g

Answer for Part (3) :

Formula used for percent yield :

$\% \text{ yield of }NH_3=\frac{\text{ Experimental yield of }NH_3}{\text{ Theoretical yield of }NH_3}\times 100$

$\% \text{ yield of }NH_3=\frac{397g}{440.96g}\times 100=90.03\%$

Therefore, the % yield of ammonia is 90.03 %

3 0

3 years ago

Which statement is true about the electrons in each polar bond of a water molecule?

Greeley [361]

They are more attracted by the oxygen atom than by the hydrogen atom.

Explanation:

In the polar bond of water which is made up of hydrogen and oxygen atoms, the shared electrons are more attracted by the oxygen atom than by the hydrogen atom.

The interatomic bond in water is a polar covalent bond.

In this bond type, two species shares their valence electrons.

The bond usually occurs between non-metals with an electronegativity difference that is small.

Oxygen is more electronegative compared to hydrogen.

This implies that oxygen pulls the electron more closely to itself since it has a greater affinity.
This leaves a partial negative charge on oxygen and a positive charge on hydrogen.
The molecule is said to be polar covalent.

learn more:

Covalent bond brainly.com/question/5258547

#learnwithBrainly

5 0

3 years ago

Read 2 more answers

The number of valence electrons in an atom with an electron configuration is 1s2 2s2 2p6 3s2 3p4

Alex_Xolod [135]

Answer:

6 valence electrons

Explanation:

The atom you have given is a sulfur atom. It has 6 valence electrons.

7 0

3 years ago

When an object reflects all light, we see (3 points) nothing white light dark blue light red light

alisha [4.7K]

When an object reflects all light, you will see white light.

8 0

3 years ago

Why is dissolving important??

Irina18 [472]

Water is called the "universal solvent" because it is capable of dissolving more substances than any other liquid. This is important to every living thing on earth. It means that wherever water goes, either through the air, the ground, or through our bodies, it takes along valuable chemicals, minerals, and nutrients.

4 0

3 years ago