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3 years ago

Who knows how to do this please help

Chemistry

1 answer:

Fofino [41]3 years ago

5 0

Answer: You forgot to zero the balance

Explanation:

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2NaCl + F2 yields 2NaF + Cl2

bearhunter [10]

Study your experiment setup. In 30 minutes, how will the air temperature in the bottles compare? What do you predict will happen to the ice in each bottle?

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3 years ago

Help pleased alot of points

JulsSmile [24]

Answer:

Nitrogen non metal

Gain 3 electrons

Negative ion N3-

Barium metal

Lose electrons

Positive charge

Selinium non metal

Gain electron

Negative charge

Cesium metal

Lose electrons

Positive charge

Explanation:

4 0

2 years ago

Is cooking raw tomatoes a physical or a chemical change? Explain why?

salantis [7]

When you are asked a question like this, you can always ask yourself this question. Can I change it back after this change? For example, if you are burning wood, you cannot bring it back to wood after you burn it, therefore, it is a chemical change. However, if you boil and evaporate water, you can make the water condense again back into its liquid form. In this case, you cannot bring the tomato back to its raw state. Therefore, cooking raw tomatoes is a chemical change.

7 0

3 years ago

How is it possible to have thousands of different proteins when there are only 20 different amino acids?

STatiana [176]

Hi there!

Although there are only 20 amino acids, these amino acids can combine into an innumerable amount of combinations to form different and unique proteins.

In case that doesn't make sense to you, I'll provide you with an analogy. You could be provided with 20 different LEGO bricks to work with. While there may only be 20 bricks, these bricks can combine into a vast amount of different formations, structures, etc. Amino Acids work in the same way.

3 0

3 years ago

Calculate ∆G ◦ r for the decomposition of mercury(II) oxide 2 HgO(s) → 2 Hg(ℓ) + O2(g) ∆H◦ f −90.83 − − (kJ · mol−1 ) ∆S ◦ m 70.

bagirrra123 [75]

Answer:

4. +117,1 kJ/mol

Explanation:

ΔG of a reaction is:

ΔGr = ΔHr - TΔSr (1)

For the reaction:

2 HgO(s) → 2 Hg(l) + O₂(g)

ΔHr: 2ΔHf Hg(l) + ΔHf O₂(g) - 2ΔHf HgO(s)

As ΔHf of Hg(l) and ΔHf O₂(g) are 0:

ΔHr: - 2ΔHf HgO(s) = 181,66 kJ/mol

In the same way ΔSr is:

ΔSr= 2ΔS° Hg(l) + ΔS° O₂(g) - 2ΔS° HgO(s)

ΔSr= 2* 76,02J/Kmol + 205,14 J/Kmol - 2*70,19 J/Kmol

ΔSr= 216,8 J/Kmol = 0,216 kJ/Kmol

Thus, ΔGr at 298K is:

ΔGr = 181,66 kJ/mol - 298K*0,216kJ/Kmol

ΔGr = +117,3 kJ/mol ≈ 4. +117,1 kJ/mol

I hope it helps!

5 0

3 years ago