<span>Assume
p=735 Torr
V= 7.6L
R=62.4
T= 295
PV-nRT
(735 Torr)(7.60L)= n (62.4Torr-Litres/mole-K)(295K)
0.30346 moles of NH3
Find moles
0.300L solution of 0.300 M HCL = 0.120 moles of HCL
0.30346 moles of NH3 reacts with 0.120 moles of HCL producing 0.120 moles of NH4+ ION, and leaving 0.18346 mole sof NH3 behind
Find molarity
0.120 moles of NH4+/0.300L = 0.400 M NH4+
0.18346 moles of NH3/0.300L = 0.6115 M NH3
NH4OH --> NH4 & OH-
Kb = [NH4+][OH]/[NH4OH]
1.8 e-5=[0.300][OH-]/[0.6115]
[OH-]=1.6e-5
pOH= 4.79
PH=9.21
.</span>
Answer:
25%
Explanation:
Half life means that 50% of the sample is gone at 3.3 years. This means that an additional 3.3 years (total 6.6 years) will reduce the sample a further 50% from the point at 3.3 years. In numbers, this means 50% of 50% (0.50*0.50), which is 25%.
freezer and refrigerator too cold for most bacteria to grow .oven too hot for bacteria to survive
Answer:
a) False
b) False
c) True
Explanation:
a) Most sulfur oxides formed during combustion come from sulfur in the air: The sulfur burns in presence of oxygen to produce sulfur oxides, the source of sulfur is anthropogenic activities (Human activities).
So the given statement is false.
b) A flue gas scrubber removes SO2 pollution in a coal-fired power plant by using lime to convert the SO2 into alcohols:
False
The lime reacts with sulfur dioxide to give carbon dioxide and calcium sulfite.
c) True
c)
Answer: Option (b) is the correct answer.
Explanation:
A solution whose constituent particles are uniformly distributed in the solution is known as a homogeneous solution.
In a homogeneous solution, particles of one solute completely dissolves in the solvent. This solution is also known a true solution.
When sand and water are mixed together then after a certain interval of time sand particles will settle at the bottom. Therefore, they do not dissolve in water. So, it is not a homogeneous solution.
When salt and water are mixed together then the salt particles will dissolve in water. Therefore, it is a homogeneous solution.
Salad dressing is not a homogeneous solution as it contains different solutions like oil, lemon juice etc which does not dissolve when mixed together.
On the other hand, soil is also not a homogeneous solution because we can visualize the distinct layers present in a soil. These layers when mixed in a solution does not dissolve so they did not form a homogeneous solution.
Thus, we can conclude that out of the given options, salt and water is a homogeneous mixture.
