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mr Goodwill [35]
3 years ago
12

Please help I’m stuck

Chemistry
1 answer:
jonny [76]3 years ago
8 0

Answer:

wouldn't it be the #2 because +∆H um I forgot

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How many double bonds are in lewis structure of oxygen difluoride, OF2? 1,0, 2, or 3​
solmaris [256]

Answer:

0

Explanation:

An image of the lewis structure of the compound OF2 is shown in the image attached.

A Lewis structure is a structure in which electron pairs on atoms are shown as dots. Sometimes shared electron pairs are shown by a horizontal straight line connecting the two atoms involved.

OF2 has no double bonds as shown in its structure. It is a compound containing only two O-F sigma bonds and no pi-bonds.

5 0
3 years ago
Calculate the atomic mass of X. The three X isotopes have atomic mass and relative abundances of 27.9769 amu (92.2297%), 28.9765
Irina18 [472]
<h3>Answer:  Si   (choice D)</h3>

This is the element Silicon.

=========================================================

Explanation:

First convert each percentage to its decimal form.

For example, 92.2297% converts to 0.922297 after moving the decimal point two spots to the left.

After doing that, multiply those decimal values with their respective atomic mass unit (amu) values.

  • 27.9769 * 0.922297 = 25.8030109393
  • 28.9765 * 0.046832 = 1.357027448
  • 29.9738 * 0.030872 = 0.9253511536

Then we add up the results

25.8030109393 + 1.357027448 + 0.9253511536 = 28.0853895409

That rounds to about 28.085

Then look at the periodic table to see the atomic mass of Cobalt (Co), Aluminum (Al), Nickel (Ni) and Silicon (Si). The mass values listed in the periodic table are weighted averages of all the isotopes. The units for the mass are still in amu.

  • Cobalt = 58.933
  • Aluminum = 26.982
  • Nickel = 58.693
  • Silicon = 28.085

We have a match with silicon, showing that <u>choice D</u> is the final answer.

7 0
1 year ago
13. An aerosol spray can of deodorant with a volume of 0.410 L contains 3.0 g of propane gas (CH3) as propellant. What is the pr
qaws [65]

Answer: The pressure in the can is 4.0 atm

Explanation:

According to ideal gas equation:

PV=nRT

P = pressure of gas = ?

V = Volume of gas = 0.410 L

n = number of moles = \frac{\text {given mass}}{\text {Molar mass}}=\frac{3.0g}{44.1g/mol}=0.068mol

R = gas constant =0.0821Latm/Kmol

T =temperature =20^0C=(20+273)K=293K

P=\frac{nRT}{V}

P=\frac0.068mol\times 0.0820 L atm/K mol\times 293K}{0.410L}=4.0atm

Thus the pressure in the can is 4.0 atm

8 0
3 years ago
At constant pressure, which of these systems do work on the surroundings? A ( s ) + B ( s ) ⟶ C ( g ) A(s)+B(s)⟶C(g) 2 A ( g ) +
Tju [1.3M]

Correct question:

At constant pressure, which of these systems do work on the surroundings?

(a) A ( s ) + B ( s ) ⟶ C ( g )

(b) 2 A ( g ) + 2 B ( g ) ⟶ 5 C ( g )

(c) A ( g ) + B ( g ) ⟶ C ( g )

(d) 2 A ( g ) + 2 B ( g ) ⟶ 3 C ( g )

Answer:

(a) A ( s ) + B ( s ) ⟶ C ( g )

(b) 2 A ( g ) + 2 B ( g ) ⟶ 5 C ( g )

Explanation:

Work done by a system on the surroundings at a constant pressure is given as;

W = -PΔV

Where;

ΔV is gas expansion, that is final volume of the gas minus initial volume of the gas must be greater than zero.

Part (a)

A ( s ) + B ( s ) ⟶ C ( g )

ΔV = 1 - (0) = 1 (expansion)

Part (b)

2 A ( g ) + 2 B ( g ) ⟶ 5 C ( g )

ΔV = 5 - ( 2+ 2) = 1 (expansion)

Part (c)

A ( g ) + B ( g ) ⟶ C ( g )

ΔV = 1 - ( 1 + 1) = -1 (compression)

Part (d)

2 A ( g ) + 2 B ( g ) ⟶ 3 C ( g )

ΔV = 3 - ( 4) = -1 (compression)

Thus, systems where there is gas expansion are in part (a) and part (b). The correct answers are:

(a) A ( s ) + B ( s ) ⟶ C ( g )

(b) 2 A ( g ) + 2 B ( g ) ⟶ 5 C ( g )

4 0
3 years ago
¿Cuál era su juego favorito cuando eran niños?​
blagie [28]

Answer:

mi juego favorito probablemente sería Mine craft cuando era más joven, aunque sigue siendo uno de mis juegos favoritos

Explanation:

7 0
3 years ago
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