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3 years ago

Give a reason for each of the following laboratory practices:

Chemistry

1 answer:

Afina-wow [57]3 years ago

5 0

Answer:

See explanation

Explanation:

The acid commonly used to acidify KMnO4 is H2SO4. The reason why HNO3 is not used is because HNO3 is itself a strong oxidizing agent. HCl is not used because it can react with KMnO4.

FeSO4 solution is usually prepared fresh when needed because if the solution is prepared and left to stand for sometime, FeSO4 is oxidized to Fe2(SO4)3 by air. Fe III does not give the brown ring test.

Alkali are not stored in glass stopped reagent bottles because very strong alkali can cause the stopper to corrode and fuse to the neck of the bottle making it very difficult to open the reagent bottle.

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What are the flocculation basins?

Mila [183]

Answer:

flocculation is the operation in which the coagulated water must be gently mixed at a propeller speed of 15 to 20 rpm to promote the growth of the floc. ... The flocculation basin often has a number of compartments with decreasing mixing speeds as the water advances through the basin.

Explanation:

8 0

3 years ago

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Write balanced chemical equation for the reactions used to prepare each of the following compounds from the given starting mater

creativ13 [48]

Explanation:

A balanced chemical equation is defined as the one that contains same number of atoms on both reactant and product side.

Whereas a chemical reaction that brings change in oxidation state of the reacting species is known as a redox reaction.

When there occurs decrease in oxidation number of an element then it shows the element has been reduced. And, if there occurs an increase in oxidation state of an element then it means the element has been oxidized.

(a) The reaction between nitrogen and hydrogen to form ammonia will be as follows.

$N_{2} + 3H_{2} \rightarrow 2NH_{3}$

So here, oxidation state of nitrogen is changing from 0 to -3. Whereas oxidation state of hydrogen is changing from 0 to +3.

Reaction between ammonia and nitric acid will be as follows.

$NH_{3} + HNO_{3} \rightarrow NH_{4}NO_{3}$

Since, it is a combination reaction. Therefore, no change in oxidation state of reacting species is taking place.

(b) Reaction for conversion of liquid bromine to hydrogen bromide is as follows.

$H_{2}(g) + Br_{2}(l) \rightarrow 2HBr(g)$

Here, oxidation state of hydrogen is changing from 0 to +1. Therefore, oxidation of hydrogen is taking place. On the other hand, oxidation state of bromine is changing from zero to -1. Therefore, reduction of bromine is taking place.

(c) Reaction between Zn and S will be as follows.

$Zn(s) + S(s) \rightarrow ZnS(s)$

Here, oxidation state of zinc is changing from 0 to +2. Hence, oxidation of zinc is taking place.

Oxidation state of sulfur is changing from 0 to -2. Therefore, reduction of sulfur is taking place.

7 0

4 years ago

Which chemical equation correctly represents the formation of water and carbon dioxide from the decomposition of carbonic acid i

defon

Carbonic acid's chemical formula is H2CO3. Its decomposition to water (H2O) and carbon dioxide (CO2) is represented by the equation:

H2CO3(g) → H2O(l) + CO2(g)

6 0

4 years ago

Read 2 more answers

g 1.000 atm of oxygen gas, placed in a container having a pinhole opening in its side, leaks from the container 2.14 times faste

Ivan

The question is incomplete, the complete question is;

1.000 atm of Oxygen gas, placed in a container having apinhole opening in its side. leaks from the container 2.14 timesfaster thatn 1.000 atm of an unknown gas placed in this sameapparatus. Which of the following species could be theunknown gas?

A. CL2

B. SF6

C. Kr

D. UF6

E. Xe

Answer:

SF6

Explanation:

From Graham's law;

Let the rate of diffusion of oxygen be R1

Let the rate of diffusion of unknown base be R2

Let the molar mass of oxygen by M1

Let the molar mass of unknown gas be M2

Hence;

R1/R2 = √M2/M1

So;

2.14/1 = √M2/32

(2.14/1)^2 = M/32

M= (2.14/1)^2 × 32

M= 146.6

This is the molar mass of SF6 hence the answer above.

7 0

3 years ago

I need help please

nika2105 [10]

Answer: No but yes if that made since

Explanation: unless every male or female suddenly leaves the facility we ain't going nowhere

6 0

3 years ago