Answer:
Mass of hydrogen gas evolved is 0.0749 grams.
Explanation:
Total pressure of the gases = p = 758 mmHg
Vapor pressure of water = 23.78 mmHg
Pressure of hydrogen gas ,P = p - 23.78 mmHg = 758 mmHg - 23.78 mmHg
P = 734.22 mmHg = 
Temperature of of hydrogen gas ,T= 25°C =298.15 K
Volume of hydrogen gas = V = 0.949 L
Moles of hydrogen gas =n
PV = nRT (Ideal gas equation )

n = 0.03745 mol
Moles of hydrogen gas = 0.03745 mol
Mass of 0.03745 moles of hydrogen gas = 0.03745 mol × 2 g/mol = 0.0749 g
Mass of hydrogen gas evolved is 0.0749 grams.
The Mass of oxygen in isolated sample is 8.6 g
<h3>What is the
Law of Constant composition?</h3>
The law of constant composition states that pure samples of the same compound contain the same element in the same ratio by mass irrespective of the source from which the compound is obtained.
Considering the given ascorbic acid samples:
Laboratory sample contains 1.50 gg of carbon and 2.00 gg of oxygen
mass ratio of oxygen to carbon is 2 : 1.5
Isolated sample will contain 2/1.5 * 6.45 g of oxygen.
Mass of oxygen in isolated sample = 8.6 g
In conclusion, the mass of oxygen is determined from the mass ratio of oxygen and carbon in the compound.
Learn more about the Law of Constant composition at: brainly.com/question/1557481
#SPJ1
Note that the complete question is given below:
A sample of ascorbic acid (vitamin C) is synthesized in the laboratory. It contains 1.50 g of carbon and 2.00 g of oxygen. Another sample of ascorbic acid isolated from citrus fruits contains 6.45 gg of carbon. According to the law of constant composition, how many grams of oxygen does this isolated sample contain?
Express the answer in grams to three significant figures.
8.47 g
Answer:
B
Explanation:
I looked it up and found the answer lol
The two main types of bonds formed between atoms are ionic bonds and covalent bonds. An ionic bond is formed when one atom accepts or donates one or more of its valence electrons to another atom. A covalent bond is formed when atoms share valence electrons.