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3 years ago

When gases are released from a reaction what type of change has occurred?

Chemistry

2 answers:

umka21 [38]3 years ago

3 0

Answer:

Color Changes. A change in color often indicates a chemical change.

Temperature Changes. Changes in temperature might also indicate a chemical change has occurred.

Precipitates. The formation of a precipitate is a sign that a chemical change has occurred.

Light Emission.

Gas Production.

Explanation:

Lesechka [4]3 years ago

3 0

Answer:

A chemical change has occurred.

Explanation:

A chemical change is accompanied by a change in the chemical composition of the substance.

A color change, formation of a precipitate, evolution of a gas , temperature change are the indications of a chemical change.

For example

$2AlCl_3 (aq)+3Na_2 CO_3 (aq)>Al_2 (CO_3 )_3 (s)+6NaCl(aq)$

Here we see the formation of a precipitate or an insoluble solid $Al_2(CO_3 )_3 (s)$

A chemical reaction is accompanied by a change in temperature.

Reaction in which heat is evolved is an exothermic reaction and reaction in which heat is absorbed is called as endothermic reaction.

Combustion reaction is an example in which heat and light is given off and it is exothermic.

Some reactions we see gas gets evolved. For example electrolysis of water produces Hydrogen and oxygen gas.

$2H_2O>2H_2+O_2$

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Because medications contains chemicals, it would dissolve into the water and not only would it pollute the water, it could flow out into areas where people are exposed to these waters.

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3 years ago

Which processes moves rock materials across the surface of the Earth?

Molodets [167]

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3 years ago

Read 2 more answers

A 100 kg tree gets struck by lightning and is burned completely to ash. A scientist gathers up all the ash and weighs it to find

Oksi-84 [34.3K]

Answer:

Evaporated via combustion.

Explanation:

The loss on ignition (LOI) and Ash content are inorganic analytical techniques used to determine the percentage by mass of hydrocarbon in compounds. This process allows volatile matter and possibly impurities found in a material to evaporate, leaving behind the true chemical constituents of the material.

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3 years ago

Please help meeeee!!!!!!!

irina [24]

Answer: Non-renewable energy comes from sources that will run out or will not be replenished in our lifetimes—or even in many, many lifetimes.

Most non-renewable energy sources are fossil fuels: coal, petroleum, and natural gas. Carbon is the main element in fossil fuels. For this reason, the time period that fossil fuels formed (about 360-300 million years ago) is called the Carboniferous Period.

All fossil fuels formed in a similar way. Hundreds of millions of years ago, even before the dinosaurs, Earth had a different landscape. It was covered with wide, shallow seas and swampy forests.

Plants, algae, and plankton grew in these ancient wetlands. They absorbed sunlight and created energy through photosynthesis. When they died, the organisms drifted to the bottom of the sea or lake. There was energy stored in the plants and animals when they died.

Over time, the dead plants were crushed under the seabed. Rocks and other sediment piled on top of them, creating high heat and pressure underground. In this environment, the plant and animal remains eventually turned into fossil fuels (coal, natural gas, and petroleum). Today, there are huge underground pockets (called reservoirs) of these non-renewable sources of energy all over the world.

Advantages and Disadvantages

Fossil fuels are a valuable source of energy. They are relatively inexpensive to extract. They can also be stored, piped, or shipped anywhere in the world.

However, burning fossil fuels is harmful for the environment. When coal and oil are burned, they release particles that can pollute the air, water, and land. Some of these particles are caught and set aside, but many of them are released into the air.

Burning fossil fuels also upsets Earth’s “carbon budget,” which balances the carbon in the ocean, earth, and air. When fossil fuels are combusted (heated), they release carbon dioxide into the atmosphere. Carbon dioxide is a gas that keeps heat in Earth’s atmosphere, a process called the “greenhouse effect.” The greenhouse effect is necessary to life on Earth, but relies on a balanced carbon budget.

The carbon in fossil fuels has been sequestered, or stored, underground for millions of years. By removing this sequestered carbon from the earth and releasing it into the atmosphere, Earth’s carbon budget is out of balance. This contributes to temperatures rising faster than organisms can adapt.

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3 years ago

The reaction below is at equilibrium at a temperature T. There are four possible changes listed. Select all the changes that wil

katovenus [111]

Answer:

The correct answer is B.

Explanation:

Heterogeneous equilibrium is that in which reagents and products are present in more than one phase.

When the reaction is carried out in a closed container, three equilibrium phases are present: solid magnesium oxide, solid magnesium sulfate and gaseous sulfur trioxide.

Hence, the equilibrium contant is given by:

$K=\frac{[MgSO_4]}{[MgO][SO_3]} =\frac{1}{[SO_3]}$

The concentrations in the equilibrium equation are the relationships of the real concentrations between the concentrations in the standard state. Since the standard state of a pure solid is the pure solid itself, the ratio of concentrations for a pure solid is equal to one.

Now, we analyse each statement:

I) As the reaction is endothermic (ΔH>0), increasing the temperature shifts the balance to the right because excess heat will be used to form more products.

II) Increasing the volume will decrease the concentration of SO₃, so Q>K and then this shifts the balance to the left.

III) As it is a heterogeneous balance, adding MgO will not affect the balance.

IV) Removing SO3 will decrease its concentration and therefore the reaction equilibrium will shift to the left.

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3 years ago