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3 years ago

how many moles of sodium are present in a sample of sodium having a mass of 137 g? (molar mass is 23.0g)

Chemistry

1 answer:

vivado [14]3 years ago

7 0

Answer:

5.95 moles

Explanation:

No of moles = given mass / molar mass

No of moles = 137/23

= 5.95 moles

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HNO3 + S --> H2SO4 + NO Now identify the element oxidized and the element reduced. Which element is oxidized? Which element i

OleMash [197]

Answer: S is getting oxidized, N is getting reduced and O and H undergo no oxidation or reduction

Explanation:

The oxidation reaction is defined as the reaction in which a chemical species loses electrons in a chemical reaction. It occurs when oxidation number of a species increases.

A reduction reaction is defined as the reaction in which a chemical species gains electrons in a chemical reaction. It occurs when oxidation number of a species decreases.

For the given chemical reaction:

$HNO_3+S\rightarrow H_2SO_4+NO$

On the reactant side:

Oxidation number of H = +1

Oxidation number of N = +5

Oxidation number of O = -2

Oxidation number of S = 0

On the product side:

Oxidation number of H = +1

Oxidation number of N = +2

Oxidation number of O = -2

Oxidation number of S = +6

As the oxidation number of S is increasing from 0 to +6. Thus, it is getting oxidized. Similarly, the oxidation number of N is decreasing from +5 to +2. Thus, it is getting reduced.

The oxidation numbers of O and H remain the same on both sides of the reaction. Thus, they are neither getting oxidized or reduced.

Hence, S is getting oxidized, N is getting reduced and O and H undergo no oxidation or reduction

3 0

2 years ago

What happens to the air in the colloid when ice cream melts

Contact [7]

The colloid formed by ice cream remains stable only at cold temperatures. When ice cream is warmed above freezing, its dispersed particles absorb energy and begin to move faster. When the fast-moving particles collide, they sometimes stick together.

7 0

3 years ago

belka [17]

Answer:

3. Inverse 1. Direct

Explanation:

P- pressure

V - volume

T - temperature

P1*V1 / T1 = P2*V2 / T2 ...... (1)

That's the general gas law with the combined ideas of charles, boyle & lussac.

Whenever you are restricted as "constant" temperature, volume, or pressure...cancel them off of your equation.

in this case 3. is indirectly telling us to cancel the temperature (T).

so we'll be left w P1*V1 = P2*V2

now notice that any relation ship that is multiplied like the one above consists of inversely related quantities. & so we conclude that-

P & V are inversely proportional or have an inverse relationship.

similarly in 1. we'll cancel p off of the general formula (1)

to be left with V1/T1 = V2/T2

also note that quantities involved in division are directly related to each other & hence the answer.

5 0

2 years ago

Why are nanowhiskers used to repel stains on fabrics??

WINSTONCH [101]

Nanowhiskers or cellulose nanofibers are nano-structured cellulose produced by bacteria. They have relatively high crystallinity and ability to form a dense network held together by inter-fibrillar bonds that has the tendency to act as a barrier through their film-forming properties to which they can repel stains on fabric.

7 0

3 years ago

If earth was a hard boiled egg,which part of earth would the egg white represent?

romanna [79]

Answer:

The egg white will represent the outer layer which is the we are located on!

Explanation:

6 0

3 years ago