All categories

3 years ago

I need help with this for science

Chemistry

1 answer:

Fantom [35]3 years ago

6 0

Answer:

Structural

Explanation:

It is a structure that those organisms have that allow it to be better suited for a task or for that organism's environment.

You might be interested in

Explain how the information given below could be used to determine the concentration of an unknown sample.

Vika [28.1K]

Answer:

See below

Explanation:Plot the known concentrations and adsorbance data. Draw a best fit line through thwe points. When the absorbance of a solution of unknown concentration (but same substance) is determined, find the concentration from the line at that absorption value. See attached graph.

E.g., an sample of the same substance had an absorbance of 0.35. Find that on the x scale and then determine the concentration that would be required to produce that level of absorbance. 0.483M in this case.

8 0

2 years ago

1. A gas having the following composition is burnt under a boiler with 50% excess air.

jeka94

The composition of the stack gas are :

$CH_4$ = 0.8713

$C_3H_8$ = 0.0202

CO = 0.107

<h3 /><h3>What is a mole fraction?</h3>

The ratio of the number of moles of one component of a solution or other mixture to the total number of moles representing all of the components.

Assuming 100 g of the stack gas. Calculate the mass of each species in this sample according to their percentages.

Mass of $CH_4$ : 70% of 100 g = 70 g

Mass of $C_3H_8$ : 15% of 100 g = 15 g

Mass of CO : 15% of 100 g = 15 g

Now calculate the number of moles of each species:

Number of moles of $CH_4$ : $\frac{70 g}{16.04 g/mol}$ = 4.3 mole

Number of moles of $C_3H_8$ : $\frac{15 g}{144.1 g/mol}$ = 0.10 mole

Mass of CO : $\frac{15 g}{28.01 g/mol}$ = 0.53 mole

Now to calculate the mole fraction of each we use the formula:

Mole fraction of $CH_4$ : $\frac{4.3}{4.935}$ = 0.8713

Mole fraction of $C_3H_8$ : $\frac{0.10}{4.935}$ = 0.0202

Mole fraction of CO : $\frac{0.53}{4.935}$ = 0.107

Hence, composition of the stack gas are:

$CH_4$ = 0.8713

$C_3H_8$ = 0.0202

CO = 0.107

Learn more about mole fraction here:

brainly.com/question/13135950

#SPJ1

8 0

3 years ago

How does a fire extinguisher works ?

Usimov [2.4K]

Answer:

Most fire extinguishers work by separating the fuel from the oxygen. The oxygen comes from the air. It is the same oxygen we breathe. Since the oxygen has to be in contact with the fuel, if you can coat the fuel with something that keeps the oxygen away, the fire will go out. Some ways of using fire extinguisher are:

 Water extinguishers work mainly by cooling (removing heat), but a dense spray of water droplets also helps to cut off oxygen.

 Dry powder extinguishers soak up heat, melt on the fuel, and cut off oxygen, but they also neutralize the fuel (cutting it off from the fire) .

Explanation:

I hope it was helpful...

8 0

2 years ago

The Mole #2 Avogadro's Number PLEASE HELP ASAP! due tmr will give brainliest!

Elis [28]

The solution is here,

given mass of copper wire(m)=25 g

no. of moles in given mass of Cu=0.393

a) no. of atoms= no. of moles×avogardo's number

=0.393×6.023×10^23=2.36 ×10^23 atoms

b) 25 g of Cu wire has 0.393 moles

so 200 g of Cu wire has 0.393/25 × 200=3.144 mol.

no. of atoms= 3.144×2.023×10^23=1.89×10^24 atoms.

c) 25 g of Cu wire has 2.36×10^23 atoms

so 5 g of Cu wire has (2.36×10^23)/25 × 5

=4.72×10^22 atoms

( b can also be solve like c)

7 0

3 years ago

A mixture is best described as:

Vesna [10]

The conglomeration of two quantities.

Two quantities that go together to become a new identity.

Here are two different definitions you can put in! Hope this helps! Please give brainliest❤️

3 0

3 years ago