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.
Answer:
<u>C) 4</u>
Explanation:
<u>The reaction</u> :
- C (s) + 2H₂ (g) ⇒ CH₄ (g)
12g 4g 16g
Hence, based on this we can say that : <u>2 moles of hydrogen gas are needed to produce 16g of methane.</u>
<u />
<u>For 32g of methane</u>
- Number of moles of H₂ = 32/16 × 2
- Number of moles of H₂ = <u>4</u>
<span>6.12<span>(<span>1024</span>)</span></span><span>=<span><span>(6.12)</span><span>(<span><span>1e</span>+24</span>)</span></span></span><span>=<span><span>6.12e</span>+24</span></span>
<span>
=
</span>
A good example is the mineral<span> plagioclase. Plagioclase is a member of the feldspar group, but </span>there<span> is more than one type of plagioclase.</span>