The answer to this would be d. Precipitation patterns .
The correct answer is a. This is because the pH of a solution is defined as -log10(concentration of H+ ions). An inverse logarithmic scale such as this means that a solution with a lower concentration of H+ ions will have a higher pH than one with a higher concentration. Therefore we know that the pH of the second sample will be higher than the first.
Since the logarithmic scale has the base 10, a change by 1 on the scale is a consequence of multiplication/division of the H+ concentration by a factor of 10. As the scale is inverse, this means that a decrease of concentration by factor 1000 is equivalent to increasing the pH by (1000/10) = 3.
To find the density of any object, you need to know the Mass (grams) of the object, and its Volume (measured in mL or cm³). Divide the mass by the volume in order to get an object's Density
We will assume that the question is discussing 1.000 atm of N₂ initially. The question is discussing diffusion rates of two gases and asks us to identify the species. We can use Graham's Law to attempt this problem with the following formula:
Rate₁/Rate₂ = sqrt(M₂/M₁)
We are told that the N₂ is 3.55 times as fast as the unknown species, so rate 1 = 3.55 and rate 2 = 1. We know the molecular weight of N₂ as 28 g/mol. Now we can use the equation above to solve for the molecular weight of the unknown, M₂:
3.55/1 = sqrt(M2/28)
(3.55)² = M₂/28
M₂ = 28 (3.55)₂
M₂ = 353 g/mol
The unknown compound has a molecular mass of roughly 353 g/mol and this is very close to the molecular mass of UF₆ which is 352.02 g/mol. Therefore, it is likely that the unknown gas is UF₆.
The type of bond that forms when two nonmetal atoms get close enough for their orbitals to overlap is called a covalent bond. Because both of these atoms are nonmetallic, neither atom has enough electronegativity to give up an electron to each other. What the atoms do, is the overlap their orbitals. The electrons in the shared orbitals can be considered to be in a covalent bond. They are held together by the attraction of both nuclei to the shared electrons.
