Answer: 3.5 moles
Explanation:
Based on Avogadro's law:
1 mole of any substance has 6.02 x 10^23 molecules
So, 1 mole of SiO4 = 6.02 x 10^23 molecules
Zmoles of SiO4 = 2.1 x 10^{24} molecules
To get the value of Z, cross multiply:
(2.1 x 10^{24} molecules x 1mole) = (6.02 x 10^23 molecules x Z moles)
2.1 x 10^{24} molecules = (6.02 x 10^23 x Z)
Z = (2.1 x 10^{24}) ➗ (6.02 x 10^23)
Z = 3.5 moles
Thus, there are 3.5 moles of SiO4.
The question is incomplete, the complete question is:
Which statements are consistent with Dalton's atomic theory as it was originally stated? Why?
a. Sulfur and oxygen atoms have the same mass.
b. All cobalt atoms are identical.
c. Potassium and chlorine atoms combine in a 1:1 ratio to form potassium chloride.
d. Lead atoms can be converted into gold.
<u>Answer: </u>The correct options are b) and c).
<u>Explanation:</u>
Some of the postulates of Dalton's atomic theory are:
- All matter is made of very tiny particles called atoms that participate in chemical reactions
- Atoms are indivisible particles that cannot be created or destroyed in a chemical reaction
- Atoms of a given element are identical in mass and chemical properties
- Atoms of different elements have different masses and chemical properties.
- Atoms combine in the ratio of small whole numbers to form compounds.
- The relative number and kinds of atoms are constant in a given compound.
For the given options:
<u>For a:</u>
The statement is inconsistent with the theory as no two elements can have the same mass. Only atoms of the same element can have the same mass.
This is consistent with the theory as atoms of the same element are identical.
This is consistent with the theory as atoms combine in a simple whole number ratio.
The statement is inconsistent with the theory as atoms of one element cannot be changed to atoms of other element.
Hence, the correct options are b) and c).
I think the correct answer is option 3. CaCl2 is the compound that is an electrolyte when dissolved in water. An electrolyte is a substance that conducts electricity in solution. Calcium Chloride when in solution dissociates into ions which allows the flow of current in the solution.
Answer: The most likely partial pressures are 98.7MPa for NO₂ and 101.3MPa for N₂O₄
Explanation: To determine the partial pressures of each gas after the increase of pressure, it can be used the equilibrium constant Kp.
For the reaction 2NO₂ ⇄ N₂O₄, the equilibrium constant is:
Kp = 
where:
P(N₂O₄) and P(NO₂) are the partial pressure of each gas.
Calculating constant:
Kp = 
Kp = 0.0104
After the weights, the total pressure increase to 200 MPa. However, at equilibrium, the constant is the same.
P(N₂O₄) + P(NO₂) = 200
P(N₂O₄) = 200 - P(NO₂)
Kp =
0.0104 = ![\frac{200 - P(NO_{2}) }{[P(NO_{2} )]^{2}}](https://tex.z-dn.net/?f=%5Cfrac%7B200%20-%20P%28NO_%7B2%7D%29%20%20%7D%7B%5BP%28NO_%7B2%7D%20%29%5D%5E%7B2%7D%7D)
0.0104![[P(NO_{2} )]^{2}](https://tex.z-dn.net/?f=%5BP%28NO_%7B2%7D%20%29%5D%5E%7B2%7D)
+ 
- 200 = 0
Resolving the second degree equation:
= 
= 98.7
Find partial pressure of N₂O₄:
P(N₂O₄) = 200 - P(NO₂)
P(N₂O₄) = 200 - 98.7
P(N₂O₄) = 101.3
The partial pressures are = 98.7 MPa and P(N₂O₄) = 101.3 MPa
D) the college students
Explanation:
In the experiment conducted by staffs of the nursing home, the group of college students that came for the experiment are the subjects of the experiment. A subject is a person that participates in a research.
- In this research, the college students are the human participants in the experiment.
- There must be a mutual agreement between the researcher and the subject because the subject is one that is being tested to see an outcome.
- A subject can quit a research if he/she deems it fit at any time.
Learn more:
Experiments brainly.com/question/5096428
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