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>
I think Intramolecular forces are being weakened
2C2H5OH + 2Na ---- 2C2H5ONa + H2
Answer:
0.7644 moles of H₂O
Explanation:
The balance chemical equation is as follow;
2 H₂O₂ → 2 H₂O + O₂
To solve this problem we will first calculate the moles of H₂O₂ as,
Moles = Mass / M/Mass
Moles = 26.0 g / 34.01 g/mol
Moles = 0.7644 mol
Secondly,
According to equation,
2 moles of H₂O₂ produces = 2 moles of H₂O
Hence,
0.7644 mol of H₂O₂ will produce = X moles of H₂O
Solving for X,
X = 2 mol × 0.7644 mol / 2 mol
X = 0.7644 moles of H₂O
