The question is incomplete, the complete question is;
A magnet was placed near a pile that contained both iron and sulfur. The magnet was moved gradually closer to the pile. As it neared the pile, the magnet started attracting small pieces of iron from the pile. Which of these statements best describes the contents of the pile?
F. It is a homogeneous mixture of iron and sulfur. G. It is a heterogeneous mixture of iron and sulfur. H. It is a compound that contains both iron and sulfur. I. It is a compound that can be separated by magnetism.
Answer:
G. It is a heterogeneous mixture of iron and sulfur.
Explanation:
A heterogeneous mixture is one that does not have a uniform composition throughout.
We must recall that a mixture is any combination of substances that do not chemically react together and are separable by physical means.
Having said this, it is clear that I can separate the iron from sulphur by simple magnetic (physical) means. Hence, it is a heterogeneous mixture of iron and sulfur.
<span>Brass, which is made by melting copper and zinc together, is harder, stronger, morecorrosion resistant and has an attractive gold colour. It still keeps its anti-bacterial properties, which makes it a great material for door knobs, handrails and plumbing fittings. Copper has been used to make coins for centuries.</span>
Divide velocity by the wavelength.
Vinegar is denser than water
Answer:
pH of resulting solution = 7.98
Explanation:
The balanced equation
HA + NaOH - Na+ + A- + H2O
Number of moles of A = Number of moles of HA = Number of moles of NaOH
= 35.8/1000 * 0.020 = 0.000716 mol
Initial concentration of A = 0.000716/0.0608 = 0.01178 M
pKb = 14 – pKa = 14 -3.9 = 10.1
Kb = 10^{-Kb} = 10^{-10.1} = 7.943 * 10^-11
Kb = [HA][OH-]/[A-]
Kb = a^2/(0.01178 -a) = 7.943 * 10^-11
a^2 + 7.943 * 10^-11 a – 9.357 * 10^-13 = 0
a = 9.673 * 10^-7
OH- = a = 9.673 * 10^-7 M
pOH = -log [OH-] = -log (9.673 * 10^-7) = 6.02
pH = 14-6.02 = 7.98
