Molality of solution = 0.529 m
mass solvent in kg = 20.6 g => 20.6 / 1000 => 0.0206 kg
number of moles = molality x mass solvent
= 0.529 x 0.0206 => <span> 0.0108 mol benzene
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hope this helps!
Answer:
115g/mol
Explanation:
To get the molar mass, we know that the it is equal to the mass divided by the number of moles. We have the mass but we do not have the number of moles.
We get this by working through the solution information. Firstly, we need to know the number of moles in 750ml for a molarity of 0.29m
Now, since 0.29 moles is present in 1000ml, x moles will be present in 750ml
The value of x is obtained as follows:
x = (750 * 0.29)/1000 = 0.2175 moles
Now since we have the number of moles, we can then obtain the molar mass.
Molar mass = mass/number of moles = 25.0g/0.2175 = 114.94 approximately 105g/mol
Answer:
There is 5.56 g of gold for every 1 g of chlorine
Explanation:
The question is to determine the simplest mass ratio of gold to Chlorine in the compound.
Since the mass of gold in the compound compared to chlorine is 15.39 g for every 2.77 g, the mass of gold per gram of chlorine is given as:
15.39 / 2.77 = 5.56 g of gold to two decimal places
<em>Therefore, for every 5.56 g of gold, there is 1 g of chlorine.</em>
<em>Note : The ratio in which different elements combine by mass to form a compound is given by the law of constant composition which states that, "all pure samples of a particular chemical compound contain the same elements combined in the same proportion by mass.</em>
Remembering the equation Q=MCdeltaT where
q=is the amount of heat energy
M=mass
C=specific heat
deltaT= change in temperature
Therefore, using the equation we can substitute values and solve for q.
Q= (15 grams) (0.129 J/(gx°C))(85-22)
Q=(15) ((0.129 J/(gx°C)) (63)
Q=121.9 Joules
The energy needed to raise the temperature of 15 grams of gold from 22 degrees Celsius to 85 degrees Celsius is then 121.9 Joules or 122 Joules (if rounded up).