Answer:
the answer would be (A.) and (D.).
Explanation:
the reason for that being is because if calcium sulfate is a main component of plaster of paris you would need to find out what is in it that makes it the main component aka (the formula) therefore part of the answer is (A.). The other part of the answer was (D.) because you would need to find the amount of calcium sulfate that contain 12 grams of oxegeon atoms because you finding the answer to that could lead to the answer of what is the main component of plaster of Paris.
Answer:
a) 320: two significant figures.
b) 2,366: four significant figures.
c) 73.0: three significant figures.
d. 532.5: four significant figures.
Explanation:
Hello there!
In this case, according to the given information, it turns out possible for us to write each number by knowing we move the decimal places to the right as much as the exponent is, and also, we count every figure, even zeros, because they are to the right of the first nonzero digit:
a) 320: two significant figures because the rightmost zero is not preceded o followed by a decimal place.
b) 2,366: four significant figures.
c) 73.0: three significant figures, because the zero is followed by the decimal place.
d. 532.5: four significant figures.
Regards!
Answer:
The answer is combustion.
Answer:
+ 291.9 kJ
Solution:
The equation given is as;
H₂O ₍s₎ → H₂ ₍g₎ + 1/2 O₂ ₍g₎ ΔH = ?
First, as we know the heat of formation of H₂O ₍l₎ is,
H₂ ₍g₎ + 1/2 O₂ ₍g₎ → H₂O ₍l₎ ΔH = - 285.9 kJ
Now, reversing the equation will reverse the sign of heat as,
H₂O ₍l₎ → H₂ ₍g₎ + 1/2 O₂ ₍g₎ ΔH = + 285.9 kJ
Also, we know that,
H₂O ₍s₎ → H₂O ₍l) ΔH = + 6.0 kJ
Now, adding last two equations,
H₂O ₍l₎ → H₂ ₍g₎ + 1/2 O₂ ₍g₎ ΔH = + 285.9 kJ
H₂O ₍s₎ → H₂O ₍l) ΔH = + 6.0 kJ
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H₂O ₍s₎ → H₂ ₍g₎ + 1/2 O₂ ₍g₎ ΔH = + 291.9 kJ
I can't see the picture, but in general, I believe it is in dropping from the first energy level above the ground state, to the ground state.
