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OverLord2011 [107]
3 years ago
5

A farmer lost most of his crops last year because of insects. This year he decided to use pesticide to kill the insects. However

, some of the insects survived the pesticide and have reproducedThe new population of insects is not affected by the pesticide. After several generations, more insects are born that survive the pesticide. What process explains the change in insect population?
A. natural selection

B. genetic engineering

C. extinction

D. artificial selection
Chemistry
1 answer:
Dominik [7]3 years ago
6 0
The answer would be natural selection I believe
You might be interested in
Please somebody give me the answers
RSB [31]

Answer:

1. 9.4 grams of methane produce<u> 25.85</u> grams of CO2

2.Grams of water produced = <u>11.81 grams</u>

3.Mass of Methane produced by 10.1 gram of O2 = <u>2.52 grams</u>

4.Amount of methane consumed = <u>46.9 grams</u>

5. Grams of Co2 produced =<u> 8.32 grams</u>

<u></u>

Explanation:

Molar masses :

Methane = CH4 = mass of C + 4x (mass of H)

CH4 = 12 +4(1) = 16 grams

<u>1 mole of CH4 = 16 gram</u>

Oxygen O2 = 2 x (mass of O) = 2x(16) = 32 gram (1 mole of O2 =32 gram)

Carbon Dioxide =CO2 = mass of C + 2(mass of O)

= 12 + 2(16)

= 44 grams <u>(1 mole of CO2 = 44 gram )</u>

Water = H2O = 18 grams ( 1 mole of H2O = 18 gram)

1 mole of each molecule is equal to their molar masses

The balanced equation is :

1CH_{4}(g)+2O_{2}\rightarrow 1CO_{2}+2H_{2}O(l)

According to Stoichiometry :

1 mole of CH4 = 2 Mole of O2 = 1 mole of CO2 = 2 mole of H2O

1. From the equation ,

1 mole of methane produce  =1 mole of CO2

16 gram of methane = 44 gram of CO2

1 gram of methane =

\frac{44}{16} gram of CO2

9.4 gram of CH4 =

\frac{44}{16}\times 9.4 gram of CO2

= 25 .85 gram of CO2

2.

2 mole of O2 produces = 2 mole of H2O(water)

1 mole of O2 produces = 1 mole of H2O

32 gram of O2 = 18 gram of water

1 gram of O2 =

\frac{18}{32}

21 gram of O2 =

\frac{18}{32}\times 21

11.81 gram of water

3. 1 mole of CH4 = 2 mole of O2

16 gram of CH4 = 2(32)  = 64 grams of O2

64 gram of O2 needs = 16 grams of CH4

1 gram of O2 needs =

\frac{16}{64}

10.1 gram of O =

\frac{16}{64}\times 10.1 of CH4

= 2.52 gram

4.

1 mole of CO2 is produced from = 1 mole of CH4

44 gram of CO2 is produced from 16 gram of CH4

1 gram CO2 =

\frac{16}{44} gram of CH4

129 gram of CO2 =

\frac{16}{44}\times 129 gram of CH4

= 46.90 grams

5.

2 mole of O2  produce = 1 mole of CO2

2x 32 gram of O2 = 44 gram of CO2

1 gram of O2 =

\frac{44}{64} of CO2

12.1 gram of O2 produce=

\frac{44}{64}\times 12.1 of CO2

= 8.318 gram

Note : Write the quantity give on left side of "="

write the substance asked on right side of "="

8 0
3 years ago
An aluminum block has a density of 2.70 g/mL. If the mass of the block is 24.60 g, find the volume of the substance.
harina [27]

Volume of a substance can be determined by dividing mass of the substance by its density.

That can be mathematical shown as:

Density=Mass/Volume

So, Volume=Mass/Density

Here mass of the substance given as 24.60 g

Whereas density of the substance is 2.70 g/mL

So,

Volume=Mass/Density

=24.6/2.7

=9.1 mL

So volume of the substance is 9.1 mL.

8 0
3 years ago
Explain why boats can float when they are made out of material that is more dense than water? Your answer must include informati
cluponka [151]
I need help to cause it asked me that questions
5 0
3 years ago
What are the characteristics of an atom or molecule when in the gas phase
Arisa [49]

Answer:vapor

Explanation: Because it is

6 0
3 years ago
Read 2 more answers
Label each transition in this flow chart as a chemical change or a physical change
Elodia [21]

1) Left up: a chemical change. We can see new substance (red-blue) is formed from one blue and one red atom.

In chemical change new substances are formed, the atoms are rearranged and the reaction is followed by an energy change.

2) Left down: a chemical change. We can see new substance (red-blue) is formed from two blue and one red atoms.

3) MIddle: a physical change. There is no new substance. Bonds are not broken.

4) Right up: a chemical change. Bonds are broken.

5) Right down: a physical change. Change of state of matter.

4 0
3 years ago
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