? I JUST DONT UNDERSTAND

the answer is : False

just did it

Answer:

Fossils?

Explanation:

Answer:

There are two dots are present on the left side of calcium atom which represents the unpaired electrons present in the outermost shell. This structure is presented by Lewis in order to show the number of unpaired electrons in the atom.

Explanation:

Answer: The coefficients are 2, 2 and 1.

Explanation: According to the law of conservation of mass, mass can neither be created nor be destroyed. Thus the mass of products has to be equal to the mass of reactants.

The number of atoms of each element has to be same on reactant and product side. Thus chemical equations are balanced.

The balanced chemical equation for the given reaction is:

2H2o➡️2h2+o2

Answer: B. It must show that the mass of each element involved is conserved  by a chemical reaction.

Explanation:

According to the law of conservation of mass, mass can neither be created nor be destroyed. Thus the mass of products has to be equal to the mass of reactants. The number of atoms of each element has to be same on reactant and product side. Thus chemical equations are balanced.

The correct statement why a chemical equation must be balanced is It must show that the mass of each element involved is conserved  by a chemical reaction.

Answer:

B. It must show that the mass of each element involved is conserved

by a chemical reaction.

Explanation:

a p e x, just took the quiz

The mass of ammonia prepared from 24.5 kg magnesium nitride, according to the reaction Mg₃N₂(s) + 6H₂O(l) → 3Mg(OH)₂(s) + 2NH₃(g), knowing that the process is 71% efficient is 5.87 kg.

The balanced reaction of production of ammonia is:

Mg₃N₂(s) + 6H₂O(l) → 3Mg(OH)₂(s) + 2NH₃(g)   (1)

First, let's find the number of moles of magnesium nitride

[tex] n_{Mg_{3}N_{2}} = \frac{m_{Mg_{3}N_{2}}}{M_{Mg_{3}N_{2}}} [/tex]  (2)

Where:

[tex]m_{Mg_{3}N_{2}}[/tex]: is the mass of Mg₃N₂ = 24.5 kg

[tex]M_{Mg_{3}N_{2}}[/tex]: is the molar mass of Mg₃N₂ = 100.9494 g/mol

The number of moles is (eq 2):

[tex] n_{Mg_{3}N_{2}} = \frac{m_{Mg_{3}N_{2}}}{M_{Mg_{3}N_{2}}} = \frac{24500 g}{100.9494 g/mol} = 242.70 \:moles [/tex]

We can calculate the mass of ammonia prepared, knowing that 1 mol of Mg₃N₂ reacts with 6 moles of H₂O to produce 3 moles of Mg(OH)₂ and 2 moles of NH₃ (reaction 1).

[tex]n_{NH_{3}} = \frac{2\: moles\: NH_{3}}{1\: mol\: Mg_{3}N_{2}}*n_{Mg_{3}N_{2} = \frac{2\: moles\: NH_{3}}{1\: mol\: Mg_{3}N_{2}}*242.70 \:moles \:Mg_{3}N_{2} = 485.4 \:moles[/tex]

Then, the mass of NH₃ is:

[tex] m_{NH_{3}} = n_{NH_{3}}*M_{NH_{3}} = 485.4 \:moles*17.031 g/mol = 8266.8 g = 8.27 kg [/tex]

Since the process is 71% efficient, the mass that can be prepared is:

[tex] m = 8.27 kg*0.71 = 5.87 kg [/tex]

Therefore, the mass of ammonia that can be prepared is 5.87 kg.

I hope it helps you!

Answer:

The answer is C. six months

Explanation:

I hope this helps you bestie:))

Answer:

3.55 x 10^23 molecules F2

Explanation:

molecules = moles x avogadro number

1 mole of gas occupies 22.4 L

moles of F2 = 13.2/22.4= 0.589 moles

moles F2 = 0.589 x 6.022 x 10^23 = 3.55 x 10^23 molecules F2

Answer:

D

Explanation:

balancing of chemical equations

Answer:

molar mass of H2CO3 = 72.0228

Answer:

62.02 g/mol

Explanation:

Took the test and got it right. if you have enough faith in brainly youll choose the right answer

Answer:

electrons are transferred from the clouds to the grounf

Explanation:

Answer:

the answer is circle 3 hope it helps

Answer:

zoo wee mama

Explanation:

The particles that make up an object are held together by bonds. Insulators have strong bonds that hold their particles rigidly in place. This prevents particles from gaining energy and increasing the temperature. Wool, dry air, plastics, and polystyrene foam are all examples of good insulators.

Answer:

The answer to the question is true.

Answer: Polarity, Boiling and Freezing Points, Specific Heat Capacity, Density, Surface Tension, Heat of Vaporization and Vapor Pressure, Capillary Action, Solid State (Ice), Liquid State (Liquid Water), Gas State (Steam),  

Explanation:  Water molecules are polar, so they form hydrogen bonds. This gives water unique properties, such as a relatively high boiling point, high specific heat, cohesion, adhesion, and density.

Answer:

Large Sharp Teeth

Explanation:

i got a 100 on my test!

Large Sharp Teeth !

i got it right on my quiz

Answer:

1. The two gases making the highest relative contribution to the greenhouse gases are: "CO2 and CH4."

2. The effect of increasing amount of greenhouse gasses is: "All of the above"

3. Which one of the following is a wrong statement?: "Eutrophication is a natural phenomenon in freshwater bodies"

4. The major contributors to the greenhouse gases are: "All of the above"

Explanation:

CO2 is carbon dioxide, and CH4 is methane. Also, the greenhouse gas effect is natural, except, the amount of greenhouse gases is not.

Answer:

A fluke because it is an vertebrae

Explanation:

Answer:

should be D. Hope this helpsss!

Answer:

The answer is 28.68 moles

Explanation:

Hope this helped Mark BRAINLEST!!!

Answer:B equals mass divided by volume

Explanation:I got hacks :)

Answer:

Which phrase describes air density? well b  

increases as altitude increases

equals mass divided by volume

pushes molecules in one direction

exerts less pressure as it increases

Explanation:

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Answer:

[tex]5.77x10^{47}particles.[/tex]

Explanation:

Hello!

In this case, since we are given 9.58x10²³ moles of potassium sulfate, it is possible to compute the particles according to the Avogadro's number:

6.022x10²³

As shown below:

[tex]9.58x10^{23}mol*\frac{6.022x10^{23}}{1mol}\\\\5.77x10^{47}particles.[/tex]

Best regards!