Answer:
The percent by mass of water in this crystal is:
Explanation:
This exercise can be easily solved using a simple rule of three where the initial weight of the hydrated crystal (6,235 g) is taken into account as 100% of the mass, and the percentage to which the mass of 4.90 g corresponds (after getting warm). First, the values and unknown variable are established:
- 6,235 g = 100%
- 4.90 g = X
And the value of the variable X is found:
- X = (4.90 g * 100%) / 6,235 g
- X = approximately 78.6%.
The calculated value is not yet the percentage of the water, since the water after heating the glass has evaporated, therefore, the remaining percentage must be taken, which can be calculated by subtraction:
- Water percentage = Total percentage - Percentage after heating.
- <u>Water percentage = 100% - 78.6% = 21.4%</u>
Answer:
89°C
Explanation:
Combined Gas Law (P₁V₁)/T₁ = (P₂V₂)/T₂
(1.25 atm)(450 mL)/(65°C) = (0.89 atm)(865 mL)/T₂
8.653846154 = 769.85/T₂
T₂ = 769.85/8.653846154
T₂ = 88.96044444 = 89°C
This problem could be solved through the Graham’s law of
effusion (also known as law of diffusion). This law states that the ratio of
the effusion rate of the first gas and effusion rate of the second gas is
equivalent to the square root of the ratio of its molar mass. Thus the answer
would be 0.1098.
Answer:
2l- ---> l2 + 2e- is the anode
2H+ + 2e- ---> H2(g) is the cathode
Explanation:
Oxidation occurs when a metal loses two or more electrons in a redox chemical reaction and reduction is when it gains. Thus, oxidation is the anode and reduction is the cathode.
