Answer: The reaction is exothermic
The 
value is negative.
Heat is a product.
Explanation:
Endothermic reactions are defined as the reactions in which energy of the product is greater than the energy of the reactants. The total energy is absorbed in the form of heat and for the reaction comes out to be positive.
Exothermic reactions are defined as the reactions in which energy of the product is lesser than the energy of the reactants. The total energy is released in the form of heat and for the reaction comes out to be negative.
The substances which are written on the left side of the arrow are reactants and the substances which are written on the right side of the arrow are products. Thus heat is a product.
The balanced chemical
reaction will be:
2H2O = 2H2 + O2
<span>We are given the amount of water used in the decomposition reaction. This will be our
starting point.</span>
<span>17.0 g H2O</span> (1 mol H2O/ 18.02 g H2O) (1 mol O2/2
mol <span>H2O</span>) ( 32.00 g O2/1mol O2) = 15.09 g O2
Percent yield = actual yield / theoretical yield x 100
<span>Percent yield =10.2 g / 15.09 g
x 100</span>
Percent yield = 67.58%
<>"Refraction is the bending of the path of a light wave as it passes from one material into another material. The refraction occurs at the boundary and is caused by a change in the speed of the light wave upon crossing the boundary. The tendency of a ray of light to bend one direction or another is dependent upon whether the light wave speeds up or slows down upon crossing the boundary. The speed of a light wave is dependent upon the optical density of the material through which it moves. For this reason, the direction that the path of a light wave bends depends on whether the light wave is traveling from a more dense (slow) medium to a less dense (fast) medium or from a less dense medium to a more dense medium. In this part of Lesson 1, we will investigate this topic of the direction of bending of a light wave.
Predicting the Direction of Bending
Recall the Marching Soldiers analogy discussed earlier in this lesson. The analogy served as a model for understanding the boundary behavior of light waves. As discussed, the analogy is often illustrated in a Physics classroom by a student demonstration. In the demonstration, a line of students (representing a light wave) marches towards a masking tape (representing the boundary) and slows down upon crossing the boundary (representative of entering a new medium). The direction of the line of students changes upon crossing the boundary. The diagram below depicts this change in direction for a line of students who slow down upon crossing the boundary.
On the diagram, the direction of the students is represented by two arrows known as rays. The direction of the students as they approach the boundary is represented by an incident ray (drawn in blue). And the direction of the students after they cross the boundary is represented by a refracted ray (drawn in red). Since the students change direction (i.e., refract), the incident ray and the refracted ray do not point in the same direction. Also, note that a perpendicular line is drawn to the boundary at the point where the incident ray strikes the boundary (i.e., masking tape). A line drawn perpendicular to the boundary at the point of incidence is known as a normal line. Observe that the refracted ray lies closer to the normal line than the incident ray does. In such an instance as this, we would say that the path of the students has bent towards the normal. We can extend this analogy to light and conclude that:
Light Traveling from a Fast to a Slow Medium
If a ray of light passes across the boundary from a material in which it travels fast into a material in which travels slower, then the light ray will bend towards the normal line.
The above principle applies to light passing from a material in which it travels fast across a boundary and into a material in which it travels slowly. But what if light wave does the opposite? What if a light wave passes from a material in which it travels slowly across a boundary and into a material in which it travels fast? The answer to this question can be answered if we reconsider the Marching Soldier analogy. Now suppose that the each individual student in the train of students speeds up once they cross the masking tape. The first student to reach the boundary will speed up and pull ahead of the other students. When the second student reaches the boundary, he/she will also speed up and pull ahead of the other students who have not yet reached the boundary. This continues for each consecutive student, causing the line of students to now be traveling in a direction further from the normal. This is depicted in the diagram below.
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Answer:
Electrons will flow from left to right through the wire.
Pb^2+ ions will be reduccd to Pb metal.
The concentration of Sn2+ ions in the left compartment will increase.
Explanation:
Looking at the relative electrode potentials of the two metals
Sn= -0.14
Pb=-0.13
Tin is expected to function as the anode (left hand half cell) and lead as the anode (right hand half cell) tin oxidizes to sn^2+ hence its concentration increases on the left compartment while lead is reduced to ordinary lead metal on the right hand half cell . since oxidation occurs on the left hand side, electrons flow from left to right.
Answer:
It's well Explained below.
Explanation:
First of Excess product of CaCO_3 would be produced due to the fact that there would not be enough CaCl_2 to react with Na_2•CO_3. The main purpose of having stoichiometric quantities is for us to know the correct amount or near the correct amount of each reactant in order to create a product that will be close to the theoretical amount and thus have a higher percent yield.
