Answer:
moles H₂O = 10
Explanation:
The mass of Na₂CO₃⋅xH₂O is 3.837 g and the mass of Na₂CO₃ is 1.42g
Therefore the mass of xH₂O is 3.837 - 1.42 = 2.417 g
The molar mass of Na₂CO₃ is 106 g/mol and for H₂O is 18 g/mol
The moles of Na₂CO₃ and H₂O in the sample are:
Na₂CO₃ = 1.42 / 106 = 0.01340 moles
H₂O = 2.417 / 18 = 0.1343
Now using rule of three :
1 mole of Na₂CO₃ has x moles of H₂O
0.01340 moles of Na₂CO₃ has 0.1343 moles of H₂O
x = 1 * 0.1343 / 0.01340 = 10
Answer: 1:4.69
Explanation:
The ratio can be expressed as:
Ua/Ub= √(Mb/Ma)
Where Ua/Ub is the ratio of velocity of hydrogen to carbon dioxide and Ma is the molecular mass of hydrogen gas= 2
Mb is the molecular mass of CO2 = 44
Therefore
Ua/Ub= √(44/2)
Ua/Ub = 4.69
Therefore the ratio of velocity of hydrogen gas to carbon dioxide = 1:4.69
which implies hydogen is about 4.69 times faster than carbon dioxide.
Answer:12 mol
Explanation: both vessels are at the same temp and pressure (and the pressure is low and/or the temperature high).
6.7mol per 1.3L = 6.7/1.3 mol/L
so in 2.33L = 6.7*2.33/1.3 = 12 mol
Taking into account the definition of avogadro's number, 3.37×10⁻⁷ moles of methane are 20.32×10¹⁶ molecules.
First of all, you have to know that Avogadro's number indicates the number of particles of a substance (usually atoms or molecules) that are in a mole.
Its value is 6.023×10²³ particles per mole and it applies to any substance.
Then you can apply the following rule of three: if 6.023×10²³ molecules are contained in 1 mole of methane, then 20.32×10¹⁶ molecules are contained in how many moles of methane?
amount of moles of methane= (20.32×10¹⁶ molecules × 1 mole)÷ 6.023×10²³ atoms
Solving:
<u><em>amount of moles of methane= 3.37×10⁻⁷ moles</em></u>
Finally, 3.37×10⁻⁷ moles of methane are 20.32×10¹⁶ molecules.
Learn more about Avogadro's Number: