1answer.
Ask question
Login Signup
Ask question
All categories
  • English
  • Mathematics
  • Social Studies
  • Business
  • History
  • Health
  • Geography
  • Biology
  • Physics
  • Chemistry
  • Computers and Technology
  • Arts
  • World Languages
  • Spanish
  • French
  • German
  • Advanced Placement (AP)
  • SAT
  • Medicine
  • Law
  • Engineering
MatroZZZ [7]
3 years ago
7

The corn crop in an area is prone to infestation by larvae from moths that feed on the cornstalks and ears of corn. The techniqu

es used by two farmers to protect the corn crop are described below.
Technique A: Sprayed his corn crop with an insecticide. The insecticide is known to kill all honeybee, butterfly, and moth larvae.
Technique B: Used a genetically modified variety of corn. The plant produces an insecticide which selectively kills only the moth larvae as it feeds on the corn.
Which technique is likely to have less of an impact on the environment?
Technique B because it preserves the harmless insects and targets only the moth larvae


Technique A because insecticide use is better for preserving the environment

Technique B because it may help humans who consume corn to fight bacA genetically engineered corn plant is approved for agricultural use.

Technique A because it kills a broader variety of insects to protect the corn
Chemistry
2 answers:
Mrac [35]3 years ago
8 0

Answer:

a

Explanation:

lozanna [386]3 years ago
7 0
Pretty sure the answer is A
You might be interested in
In atoms, electrons surround the nucleus in?
Charra [1.4K]

either the answer is  B or D

4 0
3 years ago
Read 2 more answers
A hot metal plate at 150°C has been placed in air at room temperature. Which event would most likely take place over the next fe
zubka84 [21]

Answer:

The air molecules that are surrounding the metal will speed up, and the molecules in the metal will slow down.

Explanation:

There will be a transfer of thermal energy (heat) from the hot metal plate to the surrounding air. This transfer of energy equates to a transfer of kinetic energy in the molecules. As the plate loses heat, the molecules in the plate will lose kinetic energy and slow down. As the surrounding air gains heat, the molecules will gain kinetic energy and speed up.

8 0
2 years ago
In an experiment to study the photoelectric effect, a scientist measures the kinetic energy of ejected electrons as afunction of
crimeas [40]

Answer:

a) v₀ = 4.41 × 10¹⁴ s⁻¹

b) W₀ = 176 KJ/mol of ejected electrons

c) From the graph, light of frequency less than v₀ will not cause electrons to break free from the surface of the metal. Electron kinetic energy remains at zero as long as the frequency of incident light is less than v₀.

d) When frequency of the light exceeds v₀, there is an increase of electron kinetic energy from zero steadily upwards with a constant slope. This is because, once light frequency exceeds, v₀, its energy too exceeds the work function of the metal and the electrons instantaneously gain the energy of incident light and convert this energy to kinetic energy by breaking free and going into motion. The energy keeps increasing as the energy and frequency of incident light increases and electrons gain more speed.

e) The slope of the line segment gives the Planck's constant. Explanation is in the section below.

Explanation:

The plot for this question which is attached to this solution has Electron kinetic energy on the y-axis and frequency of incident light on the x-axis.

a) Wavelength, λ = 680 nm = 680 × 10⁻⁹ m

Speed of light = 3 × 10⁸ m/s

The frequency of the light, v₀ = ?

Frequency = speed of light/wavelength

v₀ = (3 × 10⁸)/(680 × 10⁻⁹) = 4.41 × 10¹⁴ s⁻¹

b) Work function, W₀ = energy of the light photons with the wavelength of v₀ = E = hv₀

h = Planck's constant = 6.63 × 10⁻³⁴ J.s

E = 6.63 × 10⁻³⁴ × 4.41 × 10¹⁴ = 2.92 × 10⁻¹⁹J

E in J/mol of ejected electrons

Ecalculated × Avogadros constant

= 2.92 × 10⁻¹⁹ × 6.023 × 10²³

= 1.76 × 10⁵ J/mol of ejected electrons = 176 KJ/mol of ejected electrons

c) Light of frequency less than v₀ does not possess enough energy to cause electrons to break free from the metal surface. The energy of light with frequency less than v₀ is less than the work function of the metal (which is the minimum amount of energy of light required to excite electrons on metal surface enough to break free).

As evident from the graph, electron kinetic energy remains at zero as long as the frequency of incident light is less than v₀.

d) When frequency of the light exceeds v₀, there is an increase of electron kinetic energy from zero steadily upwards with a constant slope. This is because, once light frequency exceeds, v₀, its energy too exceeds the work function of the metal and the electrons instantaneously gain the energy of incident light and convert this energy to kinetic energy by breaking free and going into motion. The energy keeps increasing as the energy and frequency of incident light increases and electrons gain more speed.

e) The slope of the line segment gives the Planck's constant. From the mathematical relationship, E = hv₀,

And the slope of the line segment is Energy of ejected electrons/frequency of incident light, E/v₀, which adequately matches the Planck's constant, h = 6.63 × 10⁻³⁴ J.s

Hope this Helps!!!

5 0
3 years ago
A geologist finds a mineral sample alongside a swift flowing river. She determines the mineral is a type of Quartz. Which is tru
Minchanka [31]
I would say d or b sorry im not that good
8 0
3 years ago
Read 2 more answers
Why are iron needles used in compasses
ludmilkaskok [199]

A compass needle points north because the north pole of the magnet inside it is attracted to the south pole of Earth's built-in magnet . <u><em>And irons are heavily attracked to magnet</em></u> .So this is why iron needles used in compasses .

4 0
3 years ago
Other questions:
  • What are subscripts in a chemical formula and what do they stand for?
    6·2 answers
  • What things can the atomic radiation help us with
    12·1 answer
  • How many protons, neutrons, and electrons are present in an atom of hafnium, Hf, with a mass number of
    11·1 answer
  • 2.5 moles of sodium chloride is dissolved<br> to make 0.050 liters of solution.
    9·1 answer
  • How did lavoisier revolutionize the science in chemistry
    13·1 answer
  • What does the subscript in chemicial formulas tell you?
    7·1 answer
  • Which of the following statements is true?
    12·1 answer
  • Someone please help?!?
    8·1 answer
  • Help please it’s due in 3 minutes
    6·1 answer
  • copper hydroxide and potassium sulfate are produced when potassium hydroxide reacts with copper sulfate balanced equation
    12·1 answer
Add answer
Login
Not registered? Fast signup
Signup
Login Signup
Ask question!