Answer: Which Group 1A elements are less dense than pure water at 4 degrees C? Li Na K. How does density vary with temperature? Temperature up, density down.
Explanation:
Answer:
14 neutrons
Explanation:
Mass - Atomic Number = Neutrons
Explanation:
A period 3 element is one of the chemical elements in the third row (or period) of the periodic table of the chemical elements. The periodic table is laid out in rows to illustrate recurring (periodic) trends in the chemical behaviour of the elements as their atomic number increases: a new row is begun when the periodic table skips a row and a chemical behaviour begins to repeat, meaning that elements with similar behaviour fall into the same vertical columns. The third period contains eight elements: sodium, magnesium, aluminium, silicon, phosphorus, sulfur, chlorine, and argon. The first two, sodium and magnesium, are members of the s-block of the periodic table, while the others are members of the p-block. All of the period 3 elements occur in nature and have at least one stable isotope.[1]
Answer:
A) homotopic and B) enantiotopic
Explanation:
Protons chemically equivalent are those that have the same chemical shift, also if they are interchangeable by some symmetry operation or by a rapid chemical process.
The existence of symmetry axes, Cn, that relate to the protons results in the protons being homotopic, that is chemically equivalent in both chiral and aquiral environments.
The existence of a plane of symmetry, σ, makes the protons related by it, are enantiotopic and these protons will only be equivalent in an aquiral medium; if the medium is chiral both protons will be chemically NOT equivalent. The existence of a center of symmetry, i, in the molecule makes the related protons through it enantiotopic and therefore chemically only in the aquiral medium.
Diastereotopic protons cannot be interconverted by any symmetry operation and they are different, with different chemical displacement.
Answer:
0.3 moles /liter
Explanation:
The molar mass of Fe(NO3)3.9H2O is 403.99
40.4 g of Fe(NO3)3.9H2O is approximately equivalent to 40.4/404.4 = 0.1 moles
As each unit of the hydrated iron nitrate contributes one unit of iron(3) ions, the concentration of iron(3) ions in the solution is 0.1 moles/liter.
As each unit of the hydrated iron nitrate contributes 3 units of nitrate ions, the concentration of nitrate ions if 0.3 moles/liter.