All categories

2 years ago

How are fossil fuels used in the harvesting of fresh apples from an apple tree?

2 answers:

7 0

Answer: The correct answer is : D. Fossil fuels power the machine that shakes the tree so that the apples to the ground.

Explanation: The use of fossil fuels has been incorporated into food production since 1950 in the form of kinetic energy, pesticides, and other products used in production. Fossil fuels are non-renewable materials such as petroleum (oil and gas) and coal.

il63 [147K]2 years ago

5 0

D is the answer hope i can help u

You might be interested in

Three radioisotopes are being discussed in a chemistry class. Technetium-99m has a half-life of 6 hours. Rubidium-87 has a half-

suter [353]

B.)<span>A doctor would use technetium-99m because a short half-life indicates a quick measurement, and a geologist would use rubidium-87 because a longer half-life means that there is a longer time to measure old rock. </span>

3 0

2 years ago

Read 2 more answers

A voltaic cell consists of a nickel electrode in a solution containing Ni2+ ions, and a copper electrode in a solution containin

Marysya12 [62]

First, we write the half equations for the reduction of the chemical species present:

Cu⁺² + 2e → Cu; E° = 0.34 V
Ni⁺² + 2e → Ni; E° = - 0.23 V

In order to determine the potential of the cell, we find the difference between the two values. For this:

E(cell) = 0.34 - (-0.23)
E(cell) = 0.57 V

The second option is correct. (The difference in values is due to different values in literature, and it is negligible)

4 0

1 year ago

Draw a lewis structure for so2 in which all atoms obey the octet rule. show formal charges. do not consider ringed structures.

Aleonysh [2.5K]

Formal charge = valence electron - bonds - dots.
double bonded oxygen = 6-2-
4 so it is 0
single bonded oxygen = 6-1-6 so it is -1
sulfur = 6-3-2 so it is +1

6 0

1 year ago

The Lewis structures of four compounds are given. In the first molecule sufur is the central atom. There are two oxygen atoms bo

vesna_86 [32]

Answer:

Compound 1. Sulfur Dioxide

Compound 3. Dichloromethane

Compound 4. Phosphorus Trichloride

<em>(figure attached)</em>

Explanation:

Compound 1. Sulfur Dioxide

Polar compound

Through the Lewis structure it is confirmed that SO₂ is a polar compound, because it is an asymmetric compound having two regions of different polarity. The lower region having oxygen groups is more electronegative then the upper region.

Compound 2. Carbon Dioxide

Non polar Compound

Through the Lewis structure it is confirmed that CO₂ is a non polar compound, because it is a symmetric compound having two regions of same polarity. The left region and the right region both contains oxygen groups having same electronegativity.

Compound 3. Dichloromethane

Polar compound

Through the Lewis structure it is confirmed that CH₂Cl₂ is a polar compound, because it is an asymmetric compound having two regions of different polarity. Two chlorine atoms are attached to it and as we know that chlorine is a more electronegative element than hydrogen so it attracts the bonding pair of electrons towards itself which creates polarity.

Compound 4. Phosphorus Trichloride

Through the Lewis structure it is confirmed that PCl₃ is a polar compound, because three chlorine atoms attached to it and as we know that chlorine is a more electronegative element so it attracts the bonding pair of electrons towards itself which creates polarity.

8 0

1 year ago

When you mixed 20 grams of magnesium and an excess of nitric acid, 1.7 grams of hydrogen was actually produced. What is the perc

Kitty [74]

Based on the balanced chemical reaction presented above, every mole of magnesium (Mg) yields one mole of diatomic hydrogen (H2). When converted to masses, every 24.3 grams of magnesium yields 2 grams of hydrogen.

From the given, there are 20 grams of magnesium available for the reaction. With this amount, the expected yield of hydrogen is 1.646 grams. To calculate the percent yield, divide the actual yield to the hypothetical yield.

*The case is impossible because the actual yield is greater than the theoretical yield.

If we assume that there had been a typographical error and that the actual yield is 0.7 grams instead of 1.7 grams, the percent yield becomes 42.5%. Thus, the answer is letter E.

6 0

2 years ago

Read 2 more answers