Is na20 a stable compound, or an unstable compound?

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

Vera_Pavlovna [14]

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.

4 0

2 years ago

Which Of These Is An Indication That A Chemical Reaction Has Occurred?

nikdorinn [45]

Answer:

Correct option is D. Formation Of A Gas

Explanation

The main indication of chemical is that new substances are formed which have different composition than reactant.

Freezing of a substance: As in this case composition remained same, so we cant say, chemical reaction is take place, like when water freezes, it composition is same as water , so it is only its physical properties, not chemical.

Melting of a substance: As in this case composition remained same, so we cant say, chemical reaction is take place, like when ice melts, composition of water remained same , so it its physical properties, not chemical.

Boiling of a substance: As in this case composition remained same, so we cant say, chemical reaction is take place, like when water boils and become vapors, composition of water and vapors remained same , so it its physical properties, not chemical properties which show its chemical reaction.

Formation of gas:

In this case, chemical reaction take place. In chemical reactions, new substance are formed whose composition is different from reactants.

6 0

2 years ago

Read 2 more answers

Determine the products of this unbalanced reaction: Select all that

inn [45]

Answer:

Ba3N2

Explanation:

valency of barium is+2and nitrogen is-3.

4 0

2 years ago

What is a negatively charged ion

dem82 [27]

an electrically charged atom or group of atoms formed by the loss or gain of one or more electrons, as a cation (positive ion) , which is created by electron loss and is attracted to the cathode in electrolysis, or as an anion (negative ion) , which is created by an electron gain and is attracted to the anode.

7 0

2 years ago

Please. If you’re good at this stuff shouldn’t be too bad.

Grace [21]

Answer:

im sorry im not sure

Explanation:

7 0

2 years ago