The answer is 69.048%.
Mass of potassium dichromate (K₂Cr₂O₇) is 294 g, which is a 100%.
Given mass of chromium is 52 g. So, the mass percent of chromium in the compound is 17.687%:
52 g : x% = 294 g : 100%
x = 52 ÷ 294 × 100 %
x = 17.687%
Given mass of potassium is 39 g. <span>So, the mass percent of potassium in the compound is 13.265%:
39 g : x% = 294 g : 100%
x = </span>39 ÷ <span>294 × 100 %
x = 13.265%
Therefore, </span>the mass percent of oxygen in the compound is <span>69.048%:
100% - </span>17.687% - <span>13.265% = 69.048%.</span>
Answer:
a. Electric Energy
b. Light Energy
c. Thermal Energy
Explanation:
a. When a lamp is turned on by means of a switch, electric energy is usually used, since that is the form of energy that is generated when there is a potential difference between two points, which allows to establish an electric current, that electric current travels through the wires up to the bulb of the lamp
b. In this case a case of light energy is presented since that is the energy transported by the light and that is manifested on the matter in different ways, one of them is to remove the electrons from the metals. This is what usually happens in some types of light bulbs, that when the displacement of the electrons is promoted, a beam of light is generated.
c. The last case is a case of thermal energy, since this energy is that expressed as the total kinetic energy resulting from the random movements of atoms and molecules. This was what could happen in case b, when the beam of light was generated. This energy is released in the form of heat, and may present high temperatures.
Answer:
1) increase concentration
2) decrease the amount
3) decrease the concentration
4) it would increase
Explanation: edge 2021
<span>0.70 mol/0.250 L = 2.8 M</span>
