The answer is letter C.
Because we classify something as a star when it is: a large ball of gas that undergoes nuclear fusion. Given this definition, a comet is not a star. A comet is a ball of ice and dirt hurtling through space, it shines only because it reflects ligh
Answer:
Noble gases are nonreactive, nonmetallic elements in group 18 of the periodic table. Noble gases are the least reactive of all elements. That's because they have eight valence electrons, which fill their outer energy level.
Elements: Argon
<span>Heat from the can is making the water molecule move faster, which melts the ice.</span>
Answer:
pH = 6.999
The solution is acidic.
Explanation:
HBr is a strong acid, a very strong one.
In water, this acid is totally dissociated.
HBr + H₂O → H₃O⁺ + Br⁻
We can think pH, as - log 7.75×10⁻¹² but this is 11.1
acid pH can't never be higher than 7.
We apply the charge balance:
[H⁺] = [Br⁻] + [OH⁻]
All the protons come from the bromide and the OH⁻ that come from water.
We can also think [OH⁻] = Kw / [H⁺] so:
[H⁺] = [Br⁻] + Kw / [H⁺]
Now, our unknown is [H⁺]
[H⁺] = 7.75×10⁻¹² + 1×10⁻¹⁴ / [H⁺]
[H⁺] = (7.75×10⁻¹² [H⁺] + 1×10⁻¹⁴) / [H⁺]
This is quadratic equation: [H⁺]² - 7.75×10⁻¹² [H⁺] - 1×10⁻¹⁴
a = 1 ; b = - 7.75×10⁻¹² ; c = -1×10⁻¹⁴
(-b +- √(b² - 4ac) / (2a)
[H⁺] = 1.000038751×10⁻⁷
- log [H⁺] = pH → 6.999
A very strong acid as HBr, in this case, it is so diluted that its pH is almost neutral.
The material which is used as source for commercial production aluminum is bauxite.
The aluminum can be extracted from bauxite ore by the process of Bayer process.
In the Bayer process, bauxite ore is heated in the pressure vessel along with a caustic soda solution (sodium hydroxide) at a temperature between 150 to 200 °C. At this temperatures, the aluminium is dissolved in the solution as sodium aluminate in the extraction process. After separation of the residue by filtering, when the liquid is cooled gibbsite is precipitated and then it is seeded with fine-grained aluminum hydroxide crystals from previous extractions. The precipitation take 7-19 days without the addition of seed crystals.
This extraction process converts the aluminium oxide to soluble sodium aluminate, NaAlO2, which afterward converted into aluminum hydroxide and then into aluminum oxide.
Thus, we concluded that the material which is used as source for commercial production aluminum is bauxite ore.
learn more about ore:
brainly.com/question/10306443
#SPJ4
