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3 years ago

Look at the above table.

Chemistry

1 answer:

MariettaO [177]3 years ago

7 0

Answer:

1. A. 0

2. B. 7

3. C. 4

Explanation:

1. charge is equal to the number of protons minus the number of electrons!

2. neutrons is equal to mass number minus atomic number!

3. valence electrons equal 4!

Hope this helped you! :)

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Calculate the change in the entropy of the system and also the change in the entropy of the surroundings, and the resulting tota

Ghella [55]

Answer:

(a) Δ $S_{sys}$ = 2.881 J/K; Δ $S_{sur}$ = -2.881 J/K; total change in entropy = 0

(b)Δ $S_{sys}$ = 2.881 J/K; Δ $S_{sur}$ = 0 ; total change in entropy = 2.881 J/K

Explanation:

In the given problem, we need to calculate the change in the entropy of the system and also the change in the entropy of the surroundings, and the resulting total change in entropy, when a sample of nitrogen gas of mass 14 g at 298 K and 1.00 bar doubles its volume. We have the following variable:

mass (m) = 14 g

Temperature = 298 K

Pressure = 1.00 bar

Initial volume = $V_{1}$

Final volume = $V_{2}$ = $2V_{1}$

(a) Change in entropy of the system Δ $S_{sys}$ = $nRIn\frac{V_{2} }{V_{1} }$

where R = 8.314 J/(mol*K)

n = number of moles = mass/molar mass = 14/ 28 = 0.5 moles

Δ $S_{sys}$ = 0.5*8.314*ln2 = 2.881 J/K

Change in entropy of the surrounding Δ $S_{sur}$ = -2.881 J/K

Therefore, for a reversible process, the total change in entropy = Δ $S_{sys}$ +Δ $S_{sur}$ = 2.881 - 2.881 = 0

(b) Because entropy is a state function, we use the same procedure as in part (a). Thus, Δ $S_{sys}$ = 2.881 J/K

Since surrounding does not change in this process Δ $S_{sur}$ = 0.

total change in entropy = Δ $S_{sys}$ +Δ $S_{sur}$ = 2.881 - 0 = 2.88 J/K

Δ $S_{sys}$ = 0

Since heat energy is not transferred from the system to the surrounding

Δ $S_{sur}$ = 0

total change in entropy = Δ $S_{sys}$ +Δ $S_{sur}$ = 0

6 0

3 years ago

Roman55 [17]

Answer:

305 litres of NO gas will be produced from 916 L of NO₂

Explanation:

Given the balanced equation of the chemical reaction as follows:

3 NO₂ (g) + H₂O( l) —— 2 HNO₃ (l) + NO (g)

Under standard conditions, 3 moles of No₂ will react with 1 mole of water to produce 1 mole of NO gas.

Molar volume of a gas at STP is 22.4 L

Number of moles of NO₂ gas present in 916 L = 916/22.4 = 40.893 moles of NO₂ gas

From the mole ratio of NO₂ to NO in the equation of reaction,

Number of moles of NO that will be produced = 1/3 × 40.893 moles = 13.631 moles of NO gas

Volume of 13.631 moles of NO gas = 13.631 × 22.4

Volume of NO gas produced = 305.334L

Therefore, Volume of NO gas produced from the reaction of 916 L of NO₂ with water = 305 L

5 0

3 years ago

A sample of an ideal gas has a volume of 2.21 L at 282 K and 1.03 atm. Calculate the pressure when the volume is 1.84 L

PIT_PIT [208]

Answer:

1.33 atm

Explanation:

use general gas equation P1 V1/ T1 = P2 V2/ T2

rearrange and make P2 the subject then solve,it should give you 1.33 atm

3 0

3 years ago

Which direction does air circulate into low pressure zones in the northern and southern hemisphere

Yuri [45]

Now consider a low pressure area on a disk as shown below.A parcel of air at point A would move toward the center of the low pressure area. That movement would take it farther away from the center of the disk and therefore it would move to the west. A parcel of air at B would move toward the center of the low pressure area which would also take it closer to the center of the spinning disk where its speed is greater than the surrounding points. It would appear to move to the east. With A moving to the west and B moving to the east the line from A to B is rotating counterclockwise.

5 0

3 years ago

Read 2 more answers

Which of the following should

Sergeu [11.5K]

Answer:

warm water holds the least amount of dissolved oxygen, so I would assume the answer would be D. a small pond could heat up easily. in addition, the water is calm and not moving in a pond

4 0

3 years ago