GIVING 40 POINTS PLZ HELP!!!!!!!!

A physical change is a change in the state or properties of matter without any accompanying change in the chemical identities of the substances contained in the matter. Physical changes are observed when wax melts, when sugar dissolves in coffee, and when steam condenses into liquid water. Other examples of physical changes include magnetizing and demagnetizing metals (as is done with common anti-theft security tags) and grinding solids into powders (which can sometimes yield noticeable changes in color).

The characteristics that distinguish one substance from another are called properties. A physical property is a characteristic of matter that is not associated with a change in its chemical composition. Familiar examples of physical properties include density, color, hardness, melting and boiling points, and electrical conductivity. Some physical properties, such as density and color, may be observed without changing the physical state of the matter. Other physical properties, such as the melting temperature of iron or the freezing temperature of water, can only be observed as matter undergoes a physical change

Figure :Copper and nitric acid undergo a chemical change to form copper nitrate and brown, gaseous nitrogen dioxide. During the combustion of a match, cellulose in the match and oxygen from the air undergo a chemical change to form carbon dioxide and water vapor. Cooking red meat causes a number of chemical changes, including the oxidation of iron in myoglobin that results in the familiar red-to-brown color change.

chemical change always produces one or more types of matter that differ from the matter present before the change. The formation of rust is a chemical change because rust is a different kind of matter than the iron, oxygen, and water present before the rust formed. The explosion of nitroglycerin is a chemical change because the gases produced are very different kinds of matter from the original substance. Other examples of chemical changes include reactions that are performed in a lab (such as copper reacting with nitric acid), all forms of combustion (burning), and food being cooked, digested, or rotting. Note that the number of atoms for a given element is calculated by multiplying the coefficient of any formula containing that element by the element’s subscript in the formula. If an element appears in more than one formula on a given side of the equation, the number of atoms represented in each must be computed and then added together. For example, both product species in the example reaction, CO2 and H2O, contain the element oxygen, and so the number of oxygen atoms on the product side of the equation is

(1 CO2 molecule × 2 O atoms per CO2 molecule) + (2 H2O molecules × 1 O atom per H2O(molecule) = 4 O atoms

The equation for the reaction between methane and oxygen to yield carbon dioxide and water is confirmed to be balanced per this approach, as shown here: CH 4 + 2O2⟶CO2 + 2H2O

Element Reactants Products Balanced?

C 1×1 = 1 1×1 = 1 1 = 1, yes

H 4×1 = 4 2×2 = 4 4 = 4, yes

O 2×2 = 4 (1×2) + (2×1) = 4 4 = 4, yes

A balanced chemical equation often may be derived from a qualitative description of some chemical reaction by a fairly simple approach known as balancing by inspection. Consider as an example the decomposition of water to yield molecular hydrogen and oxygen. This process is represented qualitatively by an unbalanced chemical equation: H2O⟶H2 + O2 (unbalanced)

Comparing the number of H and O atoms on either side of this equation confirms its imbalance:

Element Reactants Products Balanced?

H 1×2 = 2 1×2 = 2 2 = 2, yes

O 1×1 = 1 1×2 = 2 1 ≠ 2, no

H2O to H2 O2 would yield balance in the number of atoms, but doing so also changes the reactant’s identity (it’s now hydrogen peroxide and not water). The O atom balance may be achieved by changing the coefficient for H2O to 2.

2H2O⟶H2 + O2 (unbalanced)

Element Reactants Products Balanced?

H 2×2 = 4 1×2 = 2 4 ≠ 2, no

O 2×1 = 2 1×2 = 2 2 = 2, yes

The H atom balance was upset by this change, but it is easily reestablished by changing the coefficient for the H2 product to 2.

2H2O⟶2H2 + O2 (balanced)

Element Reactants Products Balanced?

H 2×2 = 4 2×2 = 4 4 = 4, yes

O 2×1 = 2 1×2 = 2 2 = 2, yes

These coefficients yield equal numbers of both H and O atoms on the reactant and product sides, and the balanced equation is, therefore:

2H2O⟶2H2 + O2

Types of Chemical Reactions

Humans interact with one another in various and complex ways, and we classify these interactions according to common patterns of behavior. When two humans exchange information, we say they are communicating. When they hit each other with their fists, we say they are fighting

A photograph is shown of a yellow green opaque substance swirled through a clear, colorless liquid in a test tube.

The given communities can be ordered in the secondary succession as grass, shrubs, small trees and large tress.

The life cycle of a plant is characterized by secondary ecological succession. Secondary succession, in contrast to primary succession, is a process initiated by an occurrence such as a forest fire, harvesting, hurricane, etc. that reduces an already established ecosystem (such as a forest or a wheat field to a smaller population of species.

As a result, secondary succession occurs on preexisting soil, whereas primary succession typically takes place in a location lacking soil. Many elements, including trophic interaction, starting composition, and competition, might influence secondary succession. Trade-off with colonization

Therefore, the given communities can be ordered from the small level to higher level as grass, shrubs, small trees and large tress.

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Your question is incomplete. But your complete question is as follows:

List the given communities in a successional sequence of secondary succession? shrubs, small trees, grass, large tress.

Answer:

the submarine floats after replacing the water with the compressed air

Answer:

The submarine will rise.

Explanation:

To get a submarine to surface, the main vents in the top of the tank are closed and high-pressure compressed air is blown into the ballast tanks, forcing the water out through the flood ports at the bottom of the tank. This increases the vessel's displacement.

Answer:

i belive its a "Mold fossil"

Explanation:

Answer:

When launching a rocket in space, the rocket's fuel starts burning and is pushed downward in the form of a gas. Due to which an external force is generated on the rocket in an upward direction which is a reaction of the force of burning fuel gas.

Answer:

Mark has a speed of 6 MPS (Miles Per Hour)

Explanation:

It took mark 2 hours to ride his bike to his grandma's house, which was 12 miles away. I divided 2 by 12 and got 6. Remember this: mph = miles away ÷ time.

Answer:

Hey dude....

Explanation:

This is ur answer.....

Hope it helps!

Brainliest pls!

Follow me! :)

Answer:

lawn fertilizer, topsoil, and a diamond necklace

Explanation:

lawn fertilizer and topsoil are coming out of the ground, therefore some amount of minerals will be in them, such as iron added to it to make whatever its going on grow stronger.

a diamond necklace is a jewel that is coming out of the ground. it is categorized as a raw mineral.

I'm not 100 percent sure about the copper wire and the cell phone.

I do belive copper is a mineral.

Answer:

B

Explanation:

temperature is a characteristic of a chemical change

Answer:

This is True

Explanation:

A fossil is any remains or trace of an ancient organism. Fossils include body fossils, left behind when the soft parts have decayed away, as well as trace fossils

Answer:

a) The kinetic energy would increase. The molecules would move faster.

Answer:

Nitrogen emissions such as ammonia, nitrogen oxide and nitrous oxides contribute to particulate matter and acid rain. Nitrous oxide is a particularly potent greenhouse gas as it is over 300 times more effective at trapping heat in the atmosphere than carbon dioxide.

Explanation:

Answer:

no one can answer your question because you have shown no arrows.

Answer:

C

Explanation:

All chemical reactions will show a change in color.

Answer:

true

Explanation:

tornadoes can dogs when they are in the air which then form strong thunderstorms

Answer:

it's true ..

Explanation:

they r caused by weather conditions

Answer:

The statue is made of a metal called copper. Over time, the copper has gone through a chemical change. This is called a chemical reaction.

Explanation:

i dont think this will help...

Answer:

Chemical.

Explanation:

Pretty sure its chemical, due to it oxidising which is a chemical reaction.

it's c I believe

Explanation:

I believe

Answer: chromium and carbon monoxide

Explanation:

The correct statement about the chemical reaction is "the products have the same number atoms as the reactants."

A chemical reaction occurs when one or more reactants (also known as reactants) are changed into one or more products (also known as products).

Chemical transformation occurs as a result of this process, which involves the breaking and forming of chemical bonds.

Rust is formed when iron and oxygen combines with each other.

Only the atoms present in the reactants can end up in the products of a chemical reaction. There are no new atoms formed, and no atoms destroyed.

In a chemical reaction, the reactants and products have the same atoms, but they are rearranged during the reaction. As a result, the atoms in the products end up in various combinations. As a result, the products are new chemically distinct substances from the reactants.

Hence, the correct statement is option D.

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Answer:

Honestly, I think it is C.

Explanation:

Brazil is in the south, so that's why it is C.

hope this helped.

Answer:

b mixture

Explanation:

if you mix two or more things makes a mixture

Answer:

Vaccines

Explanation:

Answer: think a

Explanation:

Answer:

an increase in temperature showing an endothermic reaction

Explanation:

the atmospheric oxygen is supplied to the iron .An endothermic reaction is any chemical reaction that absorbs heat from its environment.

Answer:

I would say A

Explanation:

when rust forms it is a completely different substance and a chemical change is when a new substance forms, hope this helps!

Answer:

the name for CaCO3 is Calcium Carbnate, and its relations with coral reefs is that the process for making said compuond happens within coral, and is considered the building block for coral reefs.

Explanation:

hope this helps!

Answer:

The answer is C

Explanation:

Answer:

A. The tendency of an object to stay at rest or in motion.

Explanation:

Interna makes stuff stay on motion or in place.

Answer:

the tendency of an object to stay at rest or on motion