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3 years ago

What causes climate change?

2 answers:

6 0

The so-called greenhouse gases. The one most of us know is carbon dioxide, although I guess there are even more dangerous matters in there.

maw [93]3 years ago

3 0

Earth’s temperature depends on the balance between energy entering and leaving the planet’s system . When incoming energy from the sun is absorbed by the Earth system, Earth warms. When the sun’s energy is reflected back into space, Earth avoids warming. When energy is released back into space, Earth cools. Many factors, both natural and human, can cause changes in Earth’s energy balance, including: View enlarged image Models that account only for the effects of natural processes are not able to explain the warming over the past century. Models that also account for the greenhouse gases emitted by humans are able to explain this warming.
Source: USGRCP (2009) Changes in the greenhouse effect, which affects the amount of heat retained by Earth’s atmosphereVariations in the sun’s energy reaching EarthChanges in the reflectivity of Earth’s atmosphere and surface

You might be interested in

What is chemical potential energy?

tigry1 [53]

Chemical potential energy: chemical potential of a species is energy that can be absorbed or released due to a change of the particle number of the given species, in a chemical reaction or phase transition

Gasoline used as kinetic energy: the various chemicals that make up gasoline contain a large amount of chemical potential energy that is released when the gasoline is burned in a controlled way in the engine of the car. The release of that energy does two things. Some of the potential energy is transformed into work, which is used to move the car

Dynamite used as kinetic energy: the dynamite being used was most likely made of nitroglycerin. Once the dynamite explodes from a percussion force (then breaking of weak bonds to releasing the raw atom) the energy is then converted to thermal, kinetic, and sound energy.

7 0

3 years ago

Separation of mixtures and purification of chemical substances

Mnenie [13.5K]

Answer:

I don't understand what to do with this

4 0

3 years ago

If you place 1.0 L of ethanol (C2H5OH) in a small laboratory that is 3.0 m long, 2.0 m wide, and 2.0 m high, will all the alcoho

ankoles [38]

If you place 1.0 L of ethanol (C2H5OH) in a small laboratory that is 3.0 m long, 2.0 m wide, and 2.0 m high, will all the alcohol evaporate? If some liquid remains, how much will there be? The vapor pressure of ethyl alcohol at 25 °C is 59 mm Hg, and the density of the liquid at this temperature is 0.785g/cm^3 .

will all the alcohol evaporate? or none at all?

Answer:

Yes, all the ethanol present in the laboratory will evaporate since the mole of ethanol present in vapor is greater. The volume of ethanol left will therefore be zero.

Explanation:

Given that:

The volume of alcohol which is placed in a small laboratory = 1.0 L

Vapor pressure of ethyl alcohol at 25 ° C = 59 mmHg

Converting 59 mmHg to atm ; since 1 atm = 760 mmHg;

Then, we have:

= $\frac{59}{760}atm$

= 0.078 atm

Temperature = 25 ° C

= ( 25 + 273 K)

= 298 K.

Density of the ethanol = 0.785 g/cm³

The volume of laboratory = l × b × h

= 3.0 m × 2.0 m × 2.5 m

= 15 m³

Converting the volume of laboratory to liter;

since 1 m³ = 100 L; Then, we have:

15 × 1000 = 15,000 L

Using ideal gas equation to determine the moles of ethanol in vapor phase; we have:

PV = nRT

Making n the subject of the formula; we have:

$n = \frac{PV}{RT}$

$n = \frac{0.078 * 15000}{0.082*290}$

n = 47. 88 mol of ethanol

Moles of ethanol in 1.0 L bottle can be calculated as follows:

Since numbers of moles = $\frac{mass}{molar mass}$

and mass = density × vollume

Then; we can say ;

number of moles = $\frac{density*volume }{molar mass of ethanol}$

number of moles = $\frac{0.785g/cm^3*1000cm^3}{46.07g/mol}$

number of moles = $\frac{&85}{46.07}$

number of moles = 17.039 mol

Thus , all the ethanol present in the laboratory will evaporate since the mole of ethanol present in vapor is greater. The volume of ethanol left will therefore be zero.

5 0

3 years ago

In 3–5 sentences, explain why electrical wires are often constructed from metal coated with rubber, and how that is similar to m

stich3 [128]

Answer:

Covering electrical wires in plastic guarantees that the electrons flowing through the wires will not flow through your body when the wire is touched.

Explanation:

"The purpose of insulation covering the metal part of an electrical wire is to prevent accidental contact with other conductors of electricity, which might result in an unintentional electric current through those other conductors."

https://www.allaboutcircuits.com/worksheets/wire-types-and-sizes/#:~:text=Most%20electrical%20wire%20is%20covered,or%20plastic%20coating%20called%20insulation.&text=The%20purpose%20of%20insulation%20covering,current%20through%20those%20other%20conductors.

https://www.hunker.com/13414152/why-are-electrical-wires-covered-in-plastic

7 0

2 years ago

Which statement about the inner planets is TRUE?

Marrrta [24]

Answer: The inner planets have common types of rocky land forms such as mountains and volcanoes.

Explanation: Helpteaching can give you an answer key to the quiz your working on also i took the test and got it right :)

3 0

3 years ago