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3 years ago

Which of the following reactions could be used to power a battery because of the transfer of electrons?

Chemistry

1 answer:

Trava [24]3 years ago

3 0

Answer is: Zn + Cu2+ → Zn2+ + Cu.

In this chemical reaction, there is transfer of electrons from zinc (Zn) to copper (Cu). Zinc change oxidation number from 0 to +2 (lost electrons) and copper change oxidation number from +2 to 0 (gain electrons).

Oxidation half reaction: Zn⁰ → Zn²⁺ + 2e⁻.

Reduction half reaction: Cu²⁺ + 2e⁻ → Cu⁰.

In other chemical reactions, there is no change of oxidation number of elements.

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Both the codons uuu and uuc specify the amino acid phenylalanine. what is the term for this phenomenon?

kaheart [24]

This is called codon degeneracy. It is also said that the genetic code is redundant, meaning that multiple codons can code for the same amino acid, like for example CCC and CCA both coding Proline.

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3 years ago

What is the main purpose of scientific models

Viktor [21]

The main purpose of scientific methods, is to show the variations of the topic you are doing in science and how you are proving it to be that way.

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4 years ago

What do you think would happen to reef dwellers (e.g., coral, parrot fish, sea cucumbers) if the algae were not able to photosyn

Dafna1 [17]

Photosynthesis is the process wherein energy from sunlight is used to catalyze the reaction converting carbon dioxide and water to glucose. If the algae were deprived of the capability to photosynthesize then they will not be able to derive the energy from the sun into usable energy in the form of glucose and eventually will lead to death of the algae. Algae, being in the bottom of the food chain, is the primary source of food, therefore energy (in the form of sugars) of reef dwellers. Cellular respiration is the process where energy stored in sugars such as glucose is converted into usable energy in the form of adenosine triphosphate and waste products such as carbon dioxide and water is produced. Without the source of energy (algae), the reef dwellers will eventually starve and die.

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4 years ago

Which statement describes a reason to consider air a mixture? A) The major constituents of air are gaseous elements. B) The comp

umka21 [38]

The correct answer is - A) The major constituents of air are gaseous elements.

With the statement ''the major constituents of air are gaseous elements'' we can easily conclude that the air is a mixture. The reason for that is that we have a plural usage of the word element, elements, which mean that there are multiple elements that make up the air.

The air is indeed predominantly a mixture of gaseous elements. The most abundant gas in the air being the nitrogen with 78.9%, oxygen with 20.95%, argon 0.93%, and carbon dioxide 0.04%, with lesser amounts of other gases also be present in it. The water vapor is also present in the air, though it is variable, being around 1% at sea level, but only 0.4% over the entire atmosphere.

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4 years ago

How many grams of calcium chloride will be produced when 29.0 g of calcium carbonate is combined with 15.0 g of hydrochloric aci

horsena [70]

Answer:

22.7 g of CaCl₂ are produced in the reaction

Explanation:

This is the reaction:

CaCO₃ + 2HCl → CaCl₂ + CO₂ + H₂O

Now, let's determine the limiting reactant.

Let's divide the mass between the molar mass, to find out moles of each reactant.

29 g / 100.08 g/m = 0.289 of carbonate

15 g / 36.45 g/m = 0.411 of acid

1 mol of carbonate must react with 2 moles of acid

0.289 moles of carbonate will react with the double of moles (0.578)

I only have 0.411 of HCl, so the acid is the limiting reactant.

Ratio is 2:1, so I will produce the half of moles, of salt.

0.411 / 2 = 0.205 moles of CaCl₂

Mol . molar mass = mass → 0.205 m . 110.98 g/m = 22.7 g

5 0

4 years ago