Answer:
Theoretical yield = 2.5 g
Explanation:
Given data:
Mass of sodium = 79.7 g
Mass of water = 45.3 g
Theoretical yield of hydrogen gas = ?
Solution:
Chemical equation:
2Na + 2H₂O → 2NaOH + H₂
Number of moles of sodium:
Number of moles = mass/ molar mass
Number of moles = 79.7 g / 23 g/mol
Number of moles = 3.5 mol
Number of moles of water:
Number of moles = mass/ molar mass
Number of moles = 45.3 g / 18g/mol
Number of moles = 2.5 mol
Now we will compare the moles of hydrogen gas with water and sodium.
H₂O : H₂
2 : 1
2.5 : 1/2×2.5 =1.25 mol
Na : H₂
2 : 1
3.5 : 1/2×3.5 =1.75 mol
water will be limiting reactant.
Theoretical yield:
Mass = number of moles × molar mass
Mass = 1.25 mol × 2 g/mol
Mass = 2.5 g
Answer:
Explanation:
In this case, according to the Periodic table
there is 1g of hydrogen per mole. As we know that dihydrogen (H2) has two hydrogen atoms per molecule. So,there will be 2*1g hydrogen per mole=2g dihydrogen per mole.
If there is 2g dihydrogen per mole,and we have 4g,then we know that there is 2 mole dihydrogen in 4g.And for hydrogen there is 4 moles in 4g of hydrogen
Answer:
D
Explanation:
Identifying unique features of evidence
Answer:
B. Green solution density is 1.06 g/ml and blue solution density is 1.20 g/ml
Explanation:
Density is given as,
D = Mass / Volume
Red Solution,
D = 25 g / 25 mL
D = 1 g/mL
Green Solution,
D = 26.5 g / 25 mL
D = 1.06 g/mL
Yellow Solution,
D = 28.2 g / 25 mL
D = 1.128 g/mL
Blue Solution,
D = 30 g / 25 mL
D = 1.20 g/mL
