Answer: 88.2 g
Solution:
1) Chemical equation:
<span>2Al (s) + 3Fe(NO3)2 (aq) → 3Fe (s) + 2Al(NO3)3 (aq)
2) Theoretical molar ratios
2 mol Al : 3 mol Fe(NO3)2 : 3 mol Fe : 2 mol Al(NO3)3
3) Starting mass of pure iron nitrate
% = (mass of iron nitrate / mass of solution) * 100 = 87.5
=> mass of iron nitrate = 87.5 * mass of solution / 100
mass of solution = 325 g
=> mass of iron nitrate = 87.5 * 325 g / 100 = 284.375 g
4) moles of iron nitrate
moles = mass in grams / molar mass
molar mass of Fe(NO3)2 = 179.85 g/mol
moles = 284.375 g/ 179.85 g/mol = 1.58 moles Fe(NO3)2
5) proportion:
x 3 mol Fe
--------------------------- = ----------------------
1.58 mol Fe(NO3)2 3 mol Fe(NO3)2
Clear x:
x = 1.58 mol Fe
6) Convert 1.58 mol Fe into grams
mass = number of moles * atomic mass
atomic mass of iron = 55.845 g / mol
mass = 1.58 moles * 55.845 g/mol = 88.24 g
Rounded to 3 significant figures: 88.2 grams of Fe.
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Answer:
The rate law is [B]
Explanation:
In Trials 1 and 2, the concentration of B changes and A is the same so you can see how changes in B affect the rate. In this case, 0.300/0.150=2 and 7.11 x 10^-4 / 3.56 x 10^-4= 2. Since there 2^1=2, we can say that the reaction order of B is 1.
Similarly, if we look at trials 2 and 3, the concentration of B is constant, while A is changing. In this case, the rate has not changed at all with a change in concentration of A, so this means that A has 0 order.
Therefore, the rate law is just [B].
Melting points and boiling points of molecular compound are usually lower than ionic compounds. This is so as only a small amount of energy is required to overcome the weak intermolecular forces of attraction (Van de Waals forces) thus having lower m.p. and b.p.
Ionic compounds require a large amount of energy to overcome the strong electrostatic forces of attraction between the ions, hence having higher mp and bp
Answer:
the heat source must be greater than 100°C
the water must be permitted to evaporate quickly
the system must be sealed and become pressurized above atmospheric pressure
the vapor pressure must be kept below 760 mmHg
Explanation:
A superheated water is a dry form of steam in which hydrogen bonds that strongly binds the molecules of water has been overcome.
Superheated water finds application in a wide range of places. For example they are used for sterilization of clinical equipment.
- To produce steam or superheated water, the temperature of the source must be greater than the boiling temperature and less than the critical temperature at 374°C.
- Since superheated water is steam and steam is water in gaseous form. The water must be made to evaporate more quickly than it should condense back.
- High pressure and sealing the system helps to produce superheated water very fast.
- If the pressure between the vapor is kept low, water will boil faster.
Answer:
Sound waves are travelling vibrations of particles in media such as air, water or metal. So it stands to reason that they cannot travel through empty space, where there are no atoms or molecules to vibrate.
Explanation:
