Percent composition by mass of oxygen =
((16.0*6)/(40.1+2*(14.0+16.0*3)))*100%
= 58.5%
therefore, the answer is D
Answer:
The mass of water to be added is 2 pounds
Explanation:
The given parameters are;
The mass of the given solution = 2 pounds
The concentration of the given solution = 30%
The desired concentration of the solution = 15%
The mass, m of the acetic acid in the given solution = 30% × 2 pounds
m = 30/100 × 2 pounds = 0.6 pounds
To make a 15% acetic acid solution of acetic acid, the mass X of the required volume, is given as follows;
15% of X = 0.6 pounds
15/100 × X = 3/20 × 0.6 pounds
∴ The mass of the solution required X = 0.6 × 20/3 = 4 pounds
The mass of the solution that will contain 0.6 pounds of acetic acid giving a 15% acetic acid solution is 4 pounds
Therefore, the mass of water to be added to the original solution to make the a 15% acetic acid solution is 2 pounds.
<span>To solve this problem, You need to look up a picture/diagram of the electromagnetic spectrum. This will have the wave regions listed as well</span> as frequencies and wavelength.
Wavelength is distance/length of one wave, which can be calculated using frequency (hz = s^-1) and the speed of light.
2.998 x 10^8 m/s ÷ 3 x 10^19 s^-1 = 9.99 x 10^-12 m
The Frequency given falls in between X-rays and Gamma rays. The wavelength however; is in the Gama ray region.
He did experiments with combustion and gas's
