Answer:
4.48 - 6.48
Explanation:
A pH indicator works in a better way in a range of pH = pKa ± 1. That means we need to determine the pKa of the indicator propyl red to find the range over which it change its color. That is:
pKa = -log Ka
pKa = -log 3.3x10⁻⁶
pKa = 5.48
That means the range over propyl red will change from yellow to red or vice versa is:
4.48 - 6.48
Answer: 1
Explanation:
The number of times a machine increases a force exerted on it The input force will be the same as the output force.
Is there multiple choice answers
Considering the ideal gas law, a sample weighing 9.49 g occupies 68.67 L at 353 K and 2.00 atm.
Ideal gases are a simplification of real gases that is done to study them more easily. It is considered to be formed by point particles, do not interact with each other and move randomly. It is also considered that the molecules of an ideal gas, in themselves, do not occupy any volume.
An ideal gas is characterized by three state variables: absolute pressure (P), volume (V), and absolute temperature (T). The relationship between them constitutes the ideal gas law, an equation that relates the three variables if the amount of substance, number of moles n, remains constant and where R is the molar constant of the gases:
P× V = n× R× T
In this case, you know:
- P= 2 atm
- V= ?
- n=
being 2g/mole the molar mass of H2, that is, the amount of mass that a substance contains in one mole. - R= 0.082
- T= 353 K
Replacing:
2 atm× V = 4.745 moles× 0.082× 353 K
Solving:
V = (4.745 moles× 0.082× 353 K)÷ 2 atm
<u><em>V= 68.67 L</em></u>
Finally, a sample weighing 9.49 g occupies 68.67 L at 353 K and 2.00 atm.
Learn more:
Answer:
Explanation:
When I was growing up, one of the most popular cartoons was a little possum whose name was Pogo. He often said
“We have met the enemy and he is us.”
It is something Pogo said more than once. We are the problem with biodiversity being threatened.
We clear land for agriculture, not only in Canada and the United States, but in places like Brazil where it matters what is done to the environment. Those trees are the planet's lungs. Whole environmental groups are devoted to stopping the harvesting of trees that are hundreds of years old.
Our oceans have become cesspools of plastic.
Our rivers have become dumping grounds for all kinds of pollutants like paint and car tires to name just a couple.
Our landscape has been cluttered by billboards advertising things that are hundreds of miles away.
There's mining, oil, and other industries that make Mother Nature shudder every time they come near her.
