The correct answer is C. It was based on the thoughts of an early philosopher.
Explanation:
An atom is a basic and smallest unit that composes matter and that determine the properties of elements. Regarding the development of ideas related to atoms these did not begin in science but in philosophy; indeed the first person that proposed matter or elements were composed of certain smaller units was the philosophers Leucippus and his pupil Democritus in Ancient Greece, who stated atoms were eternal, infinite and defined the qualities of an object, idea that was supported by other Greek philosophers. But it was not until 16th and 17th centuries after the Middle Ages that the term re-emerged and until the 19th century it was officially proposed and there were experiments by scientists that later became a theory. Therefore, the development of the earliest idea about attoms differs from later work of scientists is that the earliest idea was based on the thoughts of an early philosopher.
Answer:
True
Explanation:
Diffusion is the movement of the particles of a substances from a region of higher concentration to a region of lower concentration.
Diffusion occurs in response to a concentration gradient.
In this case, the dye is at a higher concentration at the middle of the shallow dish of water. Diffusion causes the dye to spread out gradually thereby causing the red cloud to grow larger with time.
Answer:
3.0 moles Al₂O₃
Explanation:
We do not know which of the reactants is the limiting reactant. Therefore, you need to convert both of the given mole values into the product. This can be done using the mole-to-mole ratio made up of the balanced equation coefficients.
4 Al + 3 O₂ -----> 2 Al₂O₃
6.0 moles Al 2 moles Al₂O₃
---------------------- x ------------------------- = 3.0 moles Al₂O₃
4 moles Al
4.0 moles O₂ 2 moles Al₂O₃
---------------------- x ------------------------- = 2.7 moles Al₂O₃
3 moles O₂
As you can see, O₂ produces the smaller amount of product. This means O₂ is the limiting reactant. Remember, the limiting reactant is the reactant which runs out before the other reactant(s) are completely reacted. As such, the actual amount of Al₂O₃ produced is 2.7 moles.
However, since this problem is directly addressing how much Al₂O₃ is produced from Al, the answer you most likely are looking for is 3.0 moles Al₂O₃.
Answer:
The concentration of Cl in the solution is 1 M (option E)
Explanation:
MgCl₂ is an ionic compound, where subscript 2 indicates that it contributes 2 anions (negatively charged ions) Cl- to the solution. And you know that 0.20 moles of MgCl₂ are dissolved in water. Then, by multiplying this amount by the subscript, you get the amount of the chlorine ion Cl- that contributes the MgCl₂ compound to the solution. Then it is obtained that said compound contributes 0.40 moles of the Cl- anion.
With a thought similar to the previous case, it can be seen that in this case 0.10 mol of the ionic compound KCl is dissolved in water, and that this compound in turn contributes only a Cl- anion to the solution. Then the KCl compound provides 0.10 moles of the Cl- anion.
On the other hand, molarity is the number of moles of solute that are dissolved in a given volume. It is expressed in the units (moles/liter).
Then, the volume in which the compounds are dissolved in the corresponding unit of measure must be expressed, that is to say in L. Knowing that 1 L is 1000 mL, then 500 mL represents 0.50 L.
And knowing that the MgCl₂ compound contributes 0.40 moles of the Cl- anion while the KCl compound contributes 0.10 moles of the anion, it is possible to say that in total there are 0.50 moles of the Clons present anion in the solution.
So:
<u><em>concentration of Cl= 1 mol/L= 1 M</em></u>
<u><em>The concentration of Cl in the solution is 1 M (option E)</em></u>
Answer:
for system would be -1.53 V
Explanation:
Determination of standard reduction potential of any system is done by placing the system in cathode and a reference half cell in anode and then evaluate the cell potential. The cell potential is the standard reduction potential of the system.
So
As is equal to 0 therefore cell potential is equal to reduction potential of any system by taking hydrogen electrode as a reference.
equal to -0.76 V with respect to hydrogen
equal to 0.77 V with respect to hydrogen
Therefore standard reduction potential of system when system is taken as reference is-
= -0.76 V - 0.77 V
= -1.53 V