How many moles are in 20 grams of O₂ gas?

How does the cardiovascular system help the body get rid of waste??

Pani-rosa [81]

The answer is the rectum

4 0

2 years ago

According to the quantum-mechanical model for the hydrogen atom, which electron transition produces light with the longer wavele

LekaFEV [45]

Answer:

Explanation:

The main task here is that there are some missing gaps in the above question that needs to be filled with the appropriate answers. So, we are just going to do rewrite the answer below as we indicate the missing gaps by underlining them and making them in bold format.

SO; In the quantum-mechanical model of the hydrogen atom.

As the n level increases. the energy increases and thus levels are closer to each other. Therefore, the transition 3p→2s would have a greater energy difference than the transition from 4p→3p.

$Energy \ and \ wavelength \ are \ inversely \ proportional , \ so \ the \ \mathbf{ 4p\to 3p} \ transition \ would$ $produce \ a \ longer \ wavelength.$

3 0

2 years ago

When ethyl-2-methylpropanoate is treated with sodium ethoxide in ethanol, there is no observable reaction. Explain this observat

den301095 [7]

Answer:

No net change in reaction occurs in this nucleophilic acyl subtitution reaction

Explanation:

Sodium ethoxide in ethanol gives nucleophilic acyl substitution reaction with ethyl-2-methylpropanoate.

Here ethoxide group replaces an ethoxide group from ester through addition-ellimination pathway.

So, ultimately, the product of this reaction is identical with reactant i.e. ethyl-2-methylpropanoate is reproduced.

Hence one might observe no change during reaction as product and reactant of this reaction are same.

Mechanistic pathway has been shown below.

8 0

2 years ago

Helppppppp please please please please please

weqwewe [10]

The answer is for this question is c

8 0

3 years ago

Read 2 more answers

Select all the true statements. When an atom gains an electron, it becomes a cation. Anions carry a positive charge. The Cl− and

REY [17]

Answer:

The statements 4 and 5 are true.

Explanation:

1. When an atom gains an electron it becomes negatively charged. This negatively charged species is called anion.

A + e⁻ → A⁻ (anion)

Therefore, the statement 1 is false.

2. An anion is formed when an atom gains an electron and becomes negatively charged. Therefore, an anion is a negatively charged species.

A + e⁻ → A⁻ (anion)

Therefore, the statement 2 is false.

3. The atomic number of chlorine atom Cl is 17 and atomic number of bromine atom Br is 35.

Since, for neutral atom, the atomic number of an atom is equal to the number of electrons present in that atom.

Therefore, the number of electrons in Cl atom is 17 and the number of electrons in Br atom is 35.

When the Cl atom gains one electron it forms Cl⁻ ion and when the Br atom gains one electron it forms Br⁻ ion.

Therefore, the number of electrons in Cl⁻ ion is 17 + 1 = 18 electrons

and the number of electrons in Br⁻ ion is 35 + 1 = 36 electrons

Therefore, Cl⁻ and Br⁻ ions do not have the same number of electrons.

Therefore, the statement 3 is false.

4. When potassium atom (K) loses one electron it forms a positively charged species called potassium cation (K⁺).

K → K⁺ + e⁻

Therefore, the statement 4 is true.

5. The atomic number of Fe atom is 26.

Since, the atomic number of an atom is equal to the number of protons present in that atom.

When the Fe atom loses two electrons to form Fe²⁺ and when the Fe atom loses three electrons to form Fe³⁺ ion, the number of protons remains the same.

Therefore, the ions Fe²⁺ and Fe³⁺ have the same number of protons.

Therefore, the statement 5 is true.

6. The atomic number of copper atom Cu is 29.

Since, for neutral atom, the atomic number of an atom is equal to the number of electrons present in that atom.

Therefore, the number of electrons in Cu atom is 29

When the Cu atom loses one electron it forms Cu⁺ ion and when the Cu atom loses two electrons it forms Cu²⁺ ion.

Cu → Cu⁺ + e⁻ and Cu → Cu²⁺ + 2e⁻

Therefore, the number of electrons in Cu⁺ ion is 29 - 1 = 28 electrons

and the number of electrons in Cu²⁺ ion is 29 - 2 = 27 electrons

Therefore, Cu⁺ ion and Cu²⁺ ion do not have the same number of electrons.

Therefore, the statement 6 is false.

3 0

2 years ago