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3 years ago

Calculate the time needed for a constant current of 0.961 a to deposit 0.500 g of co(ii) as

Chemistry

1 answer:

Vera_Pavlovna [14]3 years ago

4 0

1.70 × 10³ seconds

<h3>Explanation </h3>

$\text{Co}^{2+}$ + 2 e⁻ → $\text{Co}$

It takes two moles of electrons to reduce one mole of cobalt (II) ions and deposit one mole of cobalt.

Cobalt has an atomic mass of 58.933 g/mol. 0.500 grams of Co contains $0.500 / 58.933 = 8.484\times 10^{-3} \; \text{mol}$ of Co atoms. It would take $2 \times 8.484 \times 10^{-3} = 0.01697 \; \text{mol}$ of electrons to reduce cobalt (II) ions and produce the $8.484\times 10^{-3} \; \text{mol}$ of cobalt atoms.

Refer to the Faraday's constant, each mole of electrons has a charge of around 96 485 columbs. The 0.01697 mol of electrons will have a charge of $1.637 \times 10^{3} \; \text{C}$ . A current of 0.961 A delivers 0.961 C of charge in one single second. It will take $1.637 \times 10^{3} / 0.961 = 1.70 \times 10^{3} \; \text{s}$ to transfer all these charge and deposit 0.500 g of Co.

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A particular atom contains 29 electrons, 34 neutrons, and 29 protons. what is the identity of this element and what is its atomi

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Answer:

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Explanation:

Given Data:

Number of Electrons = 29

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Number of Protons = 29

Identity and atomic number of Element:

This element can be identified by using two sources, i) Atomic Number ii) Electronic Configuration.

Atomic Number is defined as the number of protons present in the nucleus of an element. As the given number of protons are 29, therefore, the atomic number of this element is also 29.

Secondly, if the element is in neutral state then its number of protons must be equal to the number of electrons present in it. So, in neutral state this element will contain 29 electrons. Therefore, the electronic configuration is as follow,

1s², 2s², 2p⁶, 3s², 3p⁶, 4s², 3d⁹

Now using electronic configuration one can easily identify the position of this element in periodic table. As the valence shell is 4, so it belongs to period 4 and there are 9 electrons in d-subshell so it belongs to transition elemnts and transition element with 9 electrons in d shell is Copper. Also, the stable electronic configuration of copper is written as,

1s², 2s², 2p⁶, 3s², 3p⁶, 4s¹, 3d¹⁰

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3 years ago

Classify each of the following as an observation, a law, or a theory. (a) All matter is made of tiny, indestructible particles c

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Explanation:

An observation is defined as the process which explains how it is happening (qualitative) and and quantitatively able to measure something about the process.

A law is defined as a verified statement that will remain true under the mentioned circumstances as it is based on the past observations that are carefully tested.

A theory is defined as the explanation of an aspect of natural world that can be tested, modified or rejected as a result of further experiments.

Hence, the given statements are classified as follows.

(a) All matter is made of tiny, indestructible particles called atoms - Theory

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melomori [17]

Answer:

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3 years ago

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coldgirl [10]

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The loosely held orbital is 4s, therefore electron will be lost from that easily.

Now, in 3p orbital, one configuration has 5 electrons and one has 1 electron.

The configuration having 5 electrons will be more tightly held by the nucleus because it has more electrons that the one having only 1 electron. Hence, the electron will be lost easily from the configuration having $3p^1$ as the valence shell.

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3 years ago

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gizmo_the_mogwai [7]

Answer:

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Explanation:

In order to find the number of atoms we will follow these two steps;

Step 1: <u>Finding out the moles of Zn as;</u>

Moles = Mass / A. Mass

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Step 2: <u>Calculating No. of Atoms as:</u>

According to Avogadro's Law, each mole contains 6.022 × 10²³ particles. These particles can be any entity i.e. atoms, molecules, formula units, ions e.t.c. So,

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No. of Atoms = 5.05 × 10²⁴ Zn Atoms

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3 years ago