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3 years ago

PLEASE HELP ASAP!!!

Chemistry

2 answers:

Softa [21]3 years ago

6 0

1 CH4 (g) + 2 O2 (g) -----> CO2 (g) + 2H2O(l) ΔH= - 890 kJ

1 mol 2 mol

1) If ΔH has minus, it means "release". We need only "release" choices.

2) From reaction

1 mol CH4 (g) "releases" ΔH= - 890 kJ - We do not have this choice.

2 mol O2 (g) "release" ΔH= - 890 kJ, so

1 mol O2 (g) "release" ΔH= - 445 kJ

Correct answer is B.

kogti [31]3 years ago

3 0

1 CH4 (g) + 2 O2 (g) -----> CO2 (g) + 2H2O(l) ΔH= - 890 kJ
1 mol 2 mol
1)  If ΔH has minus, it means "release". We need only "release" choices.<span>
2) From reaction
1 mol </span>CH4 (g)  "releases"  ΔH= - 890 kJ - We do not have this choice.

2 mol  O2 (g)   "release" ΔH= - 890 kJ, so
1 mol  O2 (g)   "release" ΔH= - 445 kJ
Correct answer is B.

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The first thing to do is to convert surface area from the in^2 to cm^2 and also the thickness unit to cm.

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The next thing to do is to calculate the volume by using the formula below;

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Mass= 8 × 6.55 = 52.4 g.

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4 years ago

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Answer:

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