You combine 13 g of magnesium with 5 g of nitrogen to form a compound.
What is the mass percent of nitrogen in the compound?

Answers

Answer 1

Answer:

[tex]\large \boxed{28 \, \% }[/tex]

Explanation:

magnesium  + nitrogen ⟶ Product

      13 g                5 g

Mass of product = 13 g + 5 g = 18 g

The product contains 5 g of nitrogen .

[tex]\text{Percent N} = \dfrac{\text{5 g}}{\text{18 g}} \times \, 100\% = \mathbf{28 \, \%}\\\text{The percent by mass of nitrogen is $\large \boxed{\mathbf{28 \, \% }}$}[/tex]


Related Questions

A large scuba tank with a volume of 18 L is rated for a pressure of 220 bar. The tank is filled at 20 °C and contains enough air to supply 1860 L of air to a diver at a pressure of 2.37 atm (a depth of 45 feet). Was the tank filled to capacity at 20 °C?

Answers

Answer:

Yes, at 20 °C the tank was filled to full capacity

Explanation:

Given;

let initial pressure, P₁ = 2.37 atm

let initial volume, V₁ = 1860 L

let final pressure, P₂ = 220 bar = 217.123 atm

let final volume, V₂ = ?

Subject the air volume (1860 L )  at 2.37 atm to the tank rating (220 bar)

Ideal law is given by;

PV = nRT

At a fixed mole and gas temperature, the equation becomes;

P₁V₁ = P₂V₂

V₂ = (P₁V₁) / P₂

V₂ = (2.37 x 1860) / 217.123

V₂ = 20.3 L

After subjecting the air volume to tank rating, the volume of the air at 220 bar is 20.3 L which is greater than tank volume (18 L).

The extra 2.3 L can be assumed to be compressed gas volume due to the given (lower) temperature.

Thus, at 20 °C the tank was filled to full capacity.

what happens when ca no3 2 is heating it gives CaO ,NO2 and 02

Answers

Answer:

balanced equation:

2Ca(NO3)2 (aq)-----> 2CaO (s) + 4NO2 (g) + O2 (g)

So heating 2 moles of Ca(NO3)2 gives 2 moles of CaO, 4 moles of NO2 and 1 mole of O2. This is a heat decomposition reaction. It gives a white precipitate (CaO), and brown pungent gas (NO2).

Answer:

The balanced equation of the reaction is below.

Explanation:

2Ca(NO3)2 -----> 2CaO + 4NO2 + O2.

Which sequence represents the relationship between temperature and volume as explained by the kinetic-molecular
theory?
higher temperature - more kinetic energy - more space between particles - higher volume
higher temperature-less kinetic energy less space between particles - higher volume
higher temperature → more kinetic energy less space between particles > lower volume
higher temperature-less kinetic energy → more space between particles lower volume
3
and wit

Answers

Answer:

A.

Explanation:

Higher temperature - more kinetic energy - more space between particles - higher volume.

What are chemical changes of matter?

Answers

Answer:

Chemical Changes are also called Chemical Reactions. Chemical reactions involve combining different substances. The chemical reaction produces a new substance with new and different physical and chemical properties. Matter is never destroyed or created in chemical reactions.

Explanation:

Which of the following is a halogen?
O A. Neon (Ne)
B. Iodine (1)
O C. Oxygen (0)
O D. Potassium (K)

Answers

Answer:

[tex]\boxed{\mathrm{Iodine}}[/tex]

Explanation:

Halogens are elements in group 17 or 7 in the periodic table.

Iodine is a halogen.

Iodine is the halogen among the given options

In the periodic table the elements that are in group 7, are reffered to as Halogen.

They are formers of  salts as a result of their reaction  with metals.

 the halogens are composed of elements which are very  reactive among group of non-metals.

They are: Chlorine, Iodine

Oxygen belongs to group 6 and potassium can be regarded as alkaline metal

Therefore, iodine, an Halogen

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Which Group has different numbers of valence electrons?
A. Alkaline earth metals
B. Alkali metals
C. Transition metals
D. Halogens

Answers

Answer:

[tex]c. \: transition \: metals[/tex]

Transition metals (Group C) have different numbers of valence electrons compared to the other groups mentioned. Therefore option C is correct.

Transition metals (Group 3-12) have varying numbers of valence electrons. This is because their valence electrons are located in more than one energy level or subshell.

The number of valence electrons for transition metals can range from 1 to 12, depending on the specific element within the group. The varying numbers of valence electrons in transition metals contribute to their diverse chemical properties and ability to form multiple oxidation states.

Therefore, transition metals (Group C) have different numbers of valence electrons compared to the other groups mentioned.

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what is a chemical bond? an attractive force between 2 molecules

Answers

Answer:

The chemical bond between 2 molecules is called an intermolecular force.

Answer:

Chemical Bond:

Attraction between two atoms results in the formation of a bond which is called a chemical bond.

Inter molecular Forces:

Attractive Force that in between 2 molecules is called Inter molecular Forces. (Inter : Between)

example of nobel gas​

Answers

Answer:

helium , krypton,xenon,radon, argon are noble gasses

Helium Two examples would be helium and argon.

Which statement describes an electron?

Answers

Answer:

The statement that describes an electron is "It has a negative charge and is located in orbitals around the nucleus." Electrons are the smallest of the three particles that make up atoms

Explanation:

Electrons are found in shells or orbitals that surround the nucleus of an atom

Electrons are the sub-atomic particles that carry a negative charge over them. In the atom, the electrons are found in the orbitals or the shells around the nucleus. Thus, option D is correct.

What are electrons?

Electrons are the smallest sub-atomic particle that has been known to carry a negative charge and are found in the orbitals of the atom. The charge carried by an electron is 1.602 x 10⁻¹⁹ coulomb and is small than the proton and neutron.

They revolve around the nucleus in their orbits and exhibit the properties of waves and matter. The number of electrons and protons are the same in a neutral atom which makes the atomic number.

Therefore, the electrons have been known to carry a negative charge that revolves in orbit around the nucleus.

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Your question is incomplete, but most probably your full question was, Which statement describes an electron?

It has a positive charge and is located in the nucleus. It has a positive charge and is located in orbitals around the nucleus. It has a negative charge and is located in the nucleus. It has a negative charge and is located in orbitals around the nucleus

Describe how red shifts were used by cosmologists to determine that the universe was expanding. How
is this evidence for the big bang theory?

Answers

Explanation:

astronomers have discover that in general the future of a Galaxy is, the more redshift light is this mean that the further away the Galaxy are the faster they are moving this is similar to explosion where the bits moving fastest travel for furthest on the explosion redshift data provides evidence that the universe including space itself is expanding .

Which type of graph is best used to show how a measured quantity changes over time?

Box and whisker plot
Line graph
Circle graph
Histogram

Answers

Line graph; shows relationship between an independent and dependent variable. One example of an independent variable is time.

What evidence suggests that global climate change is causing the oceans to get warmer?

Answers

Answer:

A large point of evidence in this would be the rate of increase in how fast the polar ice caps are melting and the ocean is rising as a result. As the climate is getting warmer so are the oceans and this is causing the ice caps which are in the ocean.

Explanation:

Acetic acid only partially ionizes in water. A solution contains a large quantity of acetic acid dissolved in water. How can this acid solution best be described?

Answers

Answer:

The acid solution is a concentrated solution.

Explanation:

Acetic acid is a weak acid, because it ionizes partially in water as shown below:

CH3COOH + H2O —> H3O+ + CH3COO-

A solution containing a larger quantity of acetic acid is termed concentrated solution.

This is so because a concentrated solution is a solution that contains more of the solute than the solvent.

A solute is the substance which dissolves in the solvent.

A solvent is the substance which dissolves a solute.

In this case, acetic acid is the solute and water is the solvent.

Solution is simply the combination of solute and solvent

Solution => Solute + Solvent

More solute + Less solvent => Concentrated solution

Therefore, a solution containing a higher quantity of acetic acid ( i.e the solute) in water (i.e the solvent) is called a concentrated solution.

A nursing home is installing their own bulk oxygen system due to their large volume of consumption. OSHA regulation 29 CFR 1910.104(b)(2)(iii) requires owners of bulk oxygen systems to provide noncombustible surfacing in areas where liquid oxygen might leak during operation of the system or during the filling of a storage container. If the nursing home provides an asphalt surface in areas where oxygen could potentially leak, will it be in compliance with the workplace regulation regarding oxygen? Explain your answer

Answers

Answer:

NO! It would be in violation of the workplace regulation regarding oxygen.

Explanation:

Bulk oxygen systems convey liquified oxygen which is of geat use and importance in institutions like a nuirsing home.

Liquified oxygen is gaseos oxygen that has been condensed under high presures into liquid form. It is transported via a complex system of vaporizers, storage tanks and pipes around the facility it is needed. Liquified oxygen is oxygen- rich.

Asphalt is a petroleum derivative that is often used to in coating surfaces and tarring roads.

Its primry constituent is Carbon with minor constitunets like sulphur, nirogen, oxygen. As a petrolem derivative, it is very combustible.

In the event of an oxygen leak on an asphalt surtface, oxygen acting as an oxidizing agent can combine with asphalt in the presence of air, to cause a large fire.

Hence, asphalt surfacing in areas of oxygen leaks, would not be in compliance with the workplace regulation as it has the potential of causing a fire in the nursing home.    

An element A reacts with water to form a compound B which is used in white washing. On exposure to air compound B forms C. The compound C on heating forms an oxide D which on treatment with water gives back B. Identify A, B and C and D, write the balanced chemical equations for the reactions involved.

Answers

Answer:

A- Ca

B- Ca(OH)2

C-CaCO3

D- CaO

Explanation:

Element A is calcium. Calcium reacts with water to form calcium hydroxide (compound B) as follows; Ca(s) + 2H2O(l) ----> Ca(OH)2(s) + H2(g).

When exposed to air, calcium hydroxide (compound B) forms calcium trioxocarbonate IV (CaCO3) which is compound C as follows;

Ca(OH)2(s) + CO2(g) -----> CaCO3(s) + H2O(l)

On heating compound C, the oxide, CaO (D) is formed as follows;

CaCO3(s) ------> CaO(s) + CO2(g)

This oxide reacts with water to yield B again as follows;

CaO(s) + H2O(l) ----> Ca(OH)2(s)

What's the valency of sulphur for Na2SO3​

Answers

Explanation:

What are the two oxidation states of sulphur in sodium thiosulphate ? In thiosulphate, two sulphurs have oxidation state of -2 and +6. (as per suggestions). Sulphur bonded to three oxygen is considered to have +6 (Sulphur A) and other sulphur has -2 (Sulphur B).

which one of the following electronic configuration represents the element that forms simple ion with a charge of-3? (a)1s^2,2s^2,2p^6,3s^2,3p^1 (b)1s^2,2s^2,2p^6,3s^2,3p^3 (c)1s^2,2s^2,2p^6,3s^2,3p^6,3d^1,4s^2 (d)1s^2,2s^2,2p^6,3s^2,3p^6​

Answers

Answer:

(b)

Explanation:

The 3s^2, 3p^6  orbitals form  -3 charge.

This is the element phosphorous and an example of a -3 ion is in aluminium phosphide, AlP3.

The electronic configuration which represents the element forming a simple ion having with a charge of -3 is; 1s², 2s², 2p⁶, 3s², 3p³. Option B is correct.

In this electronic configuration, the element has a total of 16 electrons. To form a simple ion with a charge of -3, the element needs to gain three electrons. This is achieved by adding three extra electrons to the existing configuration.

When the element gains three electrons, the electron configuration becomes:

1s², 2s², 2p⁶, 3s², 3p⁶

This configuration represents the stable octet configuration, where the element has a complete outer shell with eight electrons. Since the charge is -3, it means the element has gained three extra electrons to achieve a stable configuration.

Therefore, the correct electronic configuration representing the element that forms a simple ion with a charge of -3 is 1s², 2s², 2p⁶, 3s², 3p³

Hence, B. is the correct option.

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Indicators change color when an acid and a base are mixed together. The change in color most likely indicates that a chemical change has occured. a physical change has occured. a new acid has been produced. a new base has been produced.

Answers

Answer:

a chemical change

Explanation:

a physical change is mostly identified even without indicators i.e candle wax about forming a new acid or base I guess we have to include a ph scale to ascertain since the salt can be acidic but not necessarily an acid

Answer: The answer is A, a chemical change has occurred

Explanation:

I’m just a jenious

in terms of bonds, what would the molecule C3H6 be classified as

Answers

Explanation:

Cyclopropane is a cycloalkane conposed of three carbon atoms to form a ring. It has a rols as an inhalation anaesthetic. It is a cycloalkane and a member of cyclopropanes.

Answer:

Alkane

Explanation:

Smaller particles in an atom are called ____________.

Answers

Answer:

[tex]\large \boxed{\sf subatomic \ particles}[/tex]

Explanation:

The smaller particles in an atom are called subatomic particles. Subatomic particles include electrons, protons, and neutrons.

An ionic bond is the attraction between _____.

Answers

Answer:

oppositely charged ions in a chemical compound

Explanation:

Answer:

Between ions

Explanation:

An atom of an element is shown by the model. A gray circle is surrounded by 4 concentric circles. The innermost circle has gray dots at the north and south positions; the second ring has 8 equally spaced dots, aligning with the inner ring at north and south; the third ring has 14 dots, equally spaced, aligned with the other rings at north and south; the outer ring has dots at north and south. How is this model useful? It shows how electrons are distributed in the shells of an iron atom. It shows how electrons are distributed in the shells of a cobalt atom. It shows how orbitals are distributed in the shells of an iron atom. It shows how orbitals are distributed in the shells of a cobalt atom.

Answers

The correct answer is A. It shows how electrons are distributed in the shells of an iron atom.

Explanation:

In the model described, the circles represent the orbitals or shells of the atom, while the dots represent the distribution of electrons (negatively charged sub-particles). Additionally, the description shows the general electronic configuration of this atom is 2, 8, 14, 2, which means in the first orbital there are two electrons, in the second there are eight electrons, in the third, there are fourteenth electrons and in the fifth orbital there are two electrons. This electronic configuration occurs in the atoms of iron. Also, this differs from Cobalt because in cobalt the third orbital has 15 electrons. Thus, the model "shows how electrons are distributed in the shells of an iron atom".

Answer:

a. it shows how electrons are distributed in the shells of an iron atom

Explanation:

edge 2021

(:

Which of the following is not true of deciduous forests?

a.
characterized by four seasons
b.
trees lose their leaves in the fall.
c.
precipitation is concentrated in one season
d.
averages 30-60 inches of precipitation annually

Answers

The Option C is correct precipitation is concentrated in the season

Hope it help

Answer:

C) precipitation is concentrated in one season

Explanation:

edge 2020

The standard reduction potential of a chromium electrode is -0.74 volts when chromium is reduced from chromium (III). The standard potential of the cell where chromium is oxidized and cerium (IV) is reduced to cerium (III) is 2.35 V. For each half reaction how many electrons are transferred

Answers

Answer:

three electrons were transferred in the process

Explanation:

The electrode potential of the cathode is

E°cathode= E°cell + E°anode

E°cathode = 2.35V + (-0.74V)

E°cathode= 1.61 V

Let us look at the reduction half equation; the oxidation half equation must be;

Oxidation half equation;

Cr(s) ----> Cr^3+(aq) + 3e

The reduction half equation must now be

Reduction half equation;

3Ce^4+(aq) + 3e ----> 3Ce^3+(aq)

This implies that three electrons were transferred in the process as shown by the balanced half cell reaction equations.

Which two features of Earth's crust involve tension?
O A. Convergent boundaries
B. Reverse faults
c. Divergent boundaries
O D. Normal faults

Answers

Answer:

The correct options are;

C. Divergent plate boundary

D. Normal faults

Explanation:

Tensile stress tends to pull objects part by acting axially upon the object to pull the object on a cross section perpendicular to the objects cross-section

The most common stress in convergent plate boundaries is compression stress

The most common stress in divergent plate boundaries is tensile stress

In the presence of tensile stress, normal faults results in the raising of mountains due to their enormous forces

Therefore, the features of Earth's crust involving tension are divergent plate boundary and normal faults.

Answer:c and d

Explanation:

What does the pH of a solution have to be in order to be a base?

Answers

Explanation:

pH is used to measure the concentration of H+ ions ([H+]) and therefore, whether a substance is acidic or basic (alkaline). Solutions with a pH of less than seven are acidic, while those with a pH greater than seven are basic (alkaline).

Answer:

greater than 7

Explanation:

A base is any solution with a pH greater than 7. A pH of 7 is considered neutral. For example, the pH of water. An acid is any solution with a pH less than 7.

Hope that helps.

May I know how to balance this

Answers

Answer:

C₅H₁₂ + 8O₂ → 5CO₂ + 6H₂O

Explanation:

Let's start by counting how many molecules we have on each side.

Reactants

C - 5

H - 12

O - 2

Products

C - 1

O - 3

H - 2

We have to balance both sides. Since we have 5 carbon atoms on the reactants side and 1 carbon atom on the products side, we'll start with that. Write 5 as the coefficient for CO₂ to balance the carbons.

C₅H₁₂ + O₂ → 5CO₂ + H₂O

Now that the carbons are balanced, let's look at the hydrogens. There's 12 on the reactants side and 2 on the products side. To balance the hydrogens, we have to write 6 as the coefficient for H₂O.

C₅H₁₂ + O₂ → 5CO₂ + 6H₂O

Now the hydrogens are balanced. All that's left to do is balance the oxygens. Let's start by counting how many atoms we have on each side.

Reactants

C - 5

H - 12

O - 2

Products

C - 5

H - 12

O - 16

So, to balance the number of atoms on both sides, write 8 as the coefficient for O₂.

C₅H₁₂ + 8O₂ → 5CO₂ + 6H₂O

Lastly, let's check to make sure everything is balanced.

Reactants

C - 5

H - 12

O - 16

Products

C - 5

O - 16

H - 12

Both sides are balanced. Therefore, the balanced chemical equation is: C₅H₁₂ + 8O₂ → 5CO₂ + 6H₂O.

Hope that helps.

Answer:

[tex]\boxed{C_{5}H_{12} + 8O_{2} -->5CO_{2} + 6H_{2}O}[/tex]

Explanation:

Part 1: Count the number of atoms on each side per element

To start, count the number of atoms per element on both sides of the equation.

Left Side

C - 5 atoms

H - 12 atoms

O - 2 atoms

Right Side

C - 1 atom

H - 2 atoms

O - 3 atoms

Part 2: Balance carbon atoms

Now, with this information, you can begin finding out how to properly balance both sides of the equation.

You need 5 carbon atoms on the left, so place a coefficient of 5 in front of the [tex]CO_{2}[/tex] product. This will balance the carbons. Do not place a coefficient in front of the [tex]C_{5}H_{12}[/tex] reactant - none are necessary!

Then, you can update your counts for your atoms.

Left Side

C - 5 atoms

H - 12 atoms

O - 2 atoms

Right Side

C - 5 atoms

H - 2 atoms

O - 11 atoms

The updated equation will look like this:

[tex]\boxed{C_{5}H_{12}+O_{2} --> 5CO_{2} + H_{2}O}[/tex]

Part 3: Balance hydrogen atoms

Now, balance the hydrogen atoms. Place a coefficient of 6 in front of the [tex]H_{2}O[/tex] product. This will balance the hydrogen atoms.

Once again, update the atom counts:

Left Side

C - 5 atoms

H - 12 atoms

O - 2 atoms

Right Side

C - 5 atoms

H - 12 atoms

O - 16 atoms

The updated equation will look like this:

[tex]\boxed{C_{5}H_{12} +O_{2}--> 5CO_{2} +6H_{2}O}[/tex]

Part 4: Balance oxygen atoms

To fully balance the equation, place a coefficient of 8 in front of the [tex]O_{2}[/tex] reactant. This will equalize the amount of oxygen atoms on both sides of the equation.

The updated equation will look like this:

[tex]\boxed{C_{5}H_{12} + 8O_{2} --> 5CO_{2} + 6H_{2}O}[/tex]

Part 5: Check the equation and atom counts

Now, update the atom counts one last time to make sure they are equal.

Left Side

C - 5 atoms

H - 12 atoms

O - 16 atoms

Right Side

C - 5 atoms

H - 12 atoms

O - 6 atoms

They are equal, so you may proceed.

Part 6: Check if reductions are necessary

If the equations coefficients can all be divided by a common divisor (i.e., 3), follow up with that step. However, any equation that has a reactant or product without a coefficient, skip this step entirely.

This equation falls into that category, so you may proceed past it.

Your final equation will look like this: [tex]\boxed{C_{5}H_{12} + 8O_{2} -->5CO_{2} + 6H_{2}O}[/tex]

distinguish between deliquescence and efflorescence. ​

Answers

Explanation:

Deliquescent substances are solids that absorb moisture from the atmosphere until they dissolve in the absorbed water and form solutions. Efflorescent: Efflorescent substances are solids that can undergo spontaneous loss of water from hydrated salts.

What is the oxidation number of carbon in CO2

Answers

Answer: Since oxygen is in group 6 on the periodic table, its valency is  

2 −

and hence so is its oxidation number.

But there are 2 oxygen atoms for each carbon atom so the total negative charge due the oxygen is  

4 −

But since a molecule must have a net charge of zero in the free form, it implies that the oxidation number of the carbon atom must then be  

+ 4

Consider a pure crystalline solid that is heated from absolute zero to a temperature above the boiling point of the liquid. Which of the following processes produces the greatest increase in the entropy of the substance?
a) melting the solid
b) heating the liquid
c) heating the gas
d) heating the solid

Answers

The question is incomplete, the complete question is;

Consider a pure crystalline solid that is heated from absolute zero to a temperature above the boiling point of the liquid. Which of the following processes produces the greatest increase in the entropy of the substance? A ) melting the solid B ) heating the gas C ) vaporizing the liquid D ) heating the solid E ) heating the liquid

Answer:

vaporizing the liquid

Explanation:

We generally define entropy in chemistry as the degree of disorderliness in a system. The entropy of gases is greater than that of liquids and the entropy of liquids is greater than that of solids. It then logically follows that the degree of entropy in gases is the greatest among all the states of matter while the entropy of solids is the least among all the states of matter since solid particles remain in their mean positions and can only vibrate or sometimes rotate. Liquid particles may translate while gaseous particles move at high velocity with negligible intermolecular forces of attraction between them.

A phase transition from liquid to gaseous state now represents the greatest change in the entropy of the system since gases posses the highest entropy among all the states of matter, hence the answer.

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Forman 1911 THE MATCH There never was a time when the world was without fire, but there was a time when men did not know how to kindle fire; and after they learned how to kindle one, it was a long, long time before they learned how to kindle one easily. In these days we can kindle a fire without any trouble, because we can easily get a match; but we must remember that the match is one of the most wonderful things in the world, and that it took men thousands of years to learn how to make one. Let us learn the history of this familiar little object, the match. Fire was first given to man by nature itself. When a forest is set on fire by cinders from a neighboring volcano, or when a tree is set ablaze by a thunderbolt, we may say that nature strikes a match. In the early history of the world, nature had to kindle all the fires, for man by his own effort was unable to produce a spark. The first method, then, of getting fire for use was to light sticks of wood at a flame kindled by natureby a volcano, perhaps, or by a stroke of lightning. These firebrands were carried to the home and used in kindling the fires there. The fire secured in this way was carefully guarded and was kept burning as long as possible. But the flame, however faithfully watched, would sometimes be extinguished. A sudden gust of wind or a sudden shower would put it out. Then a new firebrand would have to be secured, and this often meant a long journey and a deal of trouble. In 1827, John Walker, a druggist in a small English town, tipped a splint with sulphur, chlorate of potash, and sulphid of antimony, and rubbed it on sandpaper, and it burst into flame. The druggist had discovered the first friction-chemical match, the kind we use to-day. It is called friction-chemical because it is made by mixing certain chemicals together and rubbing them. Although Walker's match did not require the bottle of acid, nevertheless it was not a good one. It could be lighted only by hard rubbing, and it sputtered and threw fire in all directions. In a few years, however, phosphorus was substituted on the tip for antimony, and the change worked wonders. The match could now be lighted with very little rubbing, and it was no longer necessary to have sandpaper upon which to rub it. It would ignite when rubbed on any dry surface, and there was no longer any sputtering. This was the phosphorus match, the match with which we are so familiar. Read this sentence from the text: A sudden gust of wind or a sudden shower would put it out. How does this line develop the main idea of the essay? It shows the difficulty of depending on nature. It shows that matches were not safe. It shows how humans could not start fire. It shows how humans were careless with fire.