answer:
the student <u>who</u> answers the riddle will get the prize
explanation:
- who is the pronoun
- a pronoun is something that substitutes for a noun
A lit candle needs to draw oxygen from the air in order to continue burning. ... Thus, oxygen inside the glass jar will decrease and it gets filled with carbon dioxide, and eventually the candle's flame will Extinguish.
Answer:
b. 10 mL
Explanation:
First we <u>calculate the amount of H⁺ moles in the acid</u>:
- [H⁺] =

100 mL ⇒ 100 / 1000 = 0.100 L
- 1x10⁻⁵M * 0.100 L = 1x10⁻⁶ mol H⁺
In order to have a neutral solution we would need the same amount of OH⁻ moles.
We can use the pOH value of the strong base:
Then we <u>calculate the molar concentration of the OH⁻ species in the basic solution</u>:
- [OH⁻] =
= 1x10⁻⁴ M
If we use 10 mL of the basic solution the number of OH⁻ would be:
10 mL ⇒ 10 / 1000 = 0.010 L
- 1x10⁻⁴ M * 0.010 L = 1x10⁻⁶ mol OH⁻
It would be equal to the moles of H⁺ so the answer is b.
The answer is -60.57 = -60.6 KJ.
CaC2(s) + 2 H2O(l) ---> Ca(OH)2(s) +C2H2(g) H= -127.2 KJ
Hf C2H2 = 226.77
Hf Ca(OH)2 = -986.2
<span>Hf H2O = -285.83
Now,
</span><span>add them up. 226.77 - 986.2 + (2*285.83) = -187.77
</span><span>Add back the total enthalpy that is given in the question
-187.77+127.2 = -60.57 </span>