Answer:
Molality is 0.25 m
Explanation:
Molality → Moles of solute / kg of solvent
We need the moles of solute → 0.124 moles
22.4 g . 1 mol / 180 g = 0.124 moles
We need the mass of solvent in kg. We determine the mass of solvent with density.
Density = Mass / Volume
Mass = Density . volume → 1 g/mL . 500 mL = 500 g
If we convert the mass in g to kg → 500 g . 1kg / 1000 g = 0.5 kg
In conclussion, molality → 0.124 mol / 0.5 kg = 0.25 m
Answer;
=28.09 amu
Explanation;
In this problem, they did not give us the percentages. However, since we know the number of atoms, we can easily calculate the percentages. For example:
(460 X 100)/500 = 92%
If we do this for all three isotopes,
(460 × 25)/500 = 5 %
(460 × 15) /500 = 3%
-We get 92%, 5%, and 3%. (We'll assume these are absolute numbers for determining our significant figures).
Now the problem is just like the previous one. First convert the percentages into decimals. Then multiply those decimals by the masses and add. Here's the solution:
= (0.92) X (27.98 amu) + (0.05) X (28.98 amu) + (0.03) X (29.97 amu)
= 25.74 amu + 1.449 amu + 0.8991 amu
= 28.09 amu
It is nontoxic, nonmetallic, odorless, tasteless, colorless
Answer:
change the concentration of one reactant while keeping the other concentrations constant
Explanation:
For a given reaction;
A + B --> C + D
The reaction rate may be given as;
Rate = k[A][B]
In the above rate equation, the orders of both reactants ( A and B) is 1 . Reaction order is basically how the concentration of the reactant affect the rate of the equation.
The correct option is;
change the concentration of one reactant while keeping the other concentrations constant.
That way, one can monitor how a particular reactant affect the rate of the reaction.
