Answer:
B
Explanation:
For solving this we need a heat balance

By changing the corresponding relations, we have

By cancelling similar factor, we obtain

Which means that the change of temperature in A is twice the change of B
The quantum mechanical model is used to describe the energy and most likely location of an electron.
Answer: Option A
<u>Explanation:
</u>
The quantum mechanical model leads to the introduction of quantum numbers representing the energy levels, sub-shells, orbitals as well as spin states of the electrons. So according to the quantum numbers we can perfectly define the position and energy of any electron in an element.
According to Pauli’s principle, any two electron cannot be having same set of quantum numbers. So, using the principle quantum number, azimuthal quantum number, magnetic and spin quantum number, we can define the energy and location of an electron in the atom.
The pH indicators to be used are Phenolphthalein, Red cabbage, Bromthymol blue and Congo red.
<h3>What are pH indicators?</h3>
Indicators are substances which change color as the pH of a medium changes.
The common indicators and their pH range is as follows:
- Phenolphthalein - pH range of 8.3 and 10.5
- Red cabbage - pH 2 to 10
- Bromthymol blue - 6.0 to 7.6
- Congo red - 3.0 to 5.2
Therefore, the indicators to be used are Phenolphthalein, Red cabbage, Bromthymol blue and Congo red.
Learn more about pH indicators at: brainly.com/question/13779537
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Answer b) a to c would be considered one wavelength.
Answer:
2.8 x 10²³ molecules H₂O
1.4 x 10²³ molecules O₂
Explanation:
First, you will need the balanced chemical equation for the formation of water:
2H₂ + O₂ -> 2H₂O
This will help in determining the mole ratios between water and oxygen, which we will need later.
Let's first calculate the number of H₂O (water) molecules. This will require stoichiometry. We are also given the mass, so we must convert mass into moles, then moles into molecules. mass -> moles -> molecules
8.5 g H₂O x (1 mol H₂O/18.01528 g H₂O) x (6.02 x 10²³ molecules H₂O/1 mol H₂O) = 2.8404 x 10²³ molecules H₂O
Rounded to 2 significant digits: 2.8 x 10²³ molecules H₂O
Now, to find the molecules of water, we can begin with the same stoichiometric equation, but before we convert to molecules, we will have to convert moles of water to moles of oxygen. This is where we will use the mole ratio of water to oxygen we got from the balanced chemical equation earlier. 2H₂O:1O₂
8.5 g H₂O x (1 mol H₂O/18.01528 g H₂O) x (1 mol O₂/2 mol H₂O) x (6.02 x 10²³ molecules O₂/1 mol O₂) = 1.4202 x 10²³ molecules O₂
Rounded to 2 significant digits: 1.4 x 10²³ molecules O₂