The first answer choice is correct: SF6 is a compound: it is a substance composed of more than one atom from different elements (sulfur and fluorine).
The second answer choice is incorrect: while SF6 is indeed a compound that contains seven atoms, those atoms are not identical since one is a sulfur atom and six are fluoride atoms.
The third answer choice is incorrect: SF6 is not an element because it can be separated chemically into simpler substances that are elements. All the atoms comprising an element must have the same number of protons (the same atomic number); sulfur and fluorine have different atomic numbers. There is no single nucleus in SF6; the S and six F atoms each has their own nucleus.
The fourth answer choice is incorrect; SF6 contains no carbon atom, and so wouldn’t meet a central criterion for an organic compound. Moreover, the formula SF6 indicates that the sulfur atom is not bonded to any other atom apart from fluorine atoms, and there are no bonding electrons left on the S. There is no plausible reason to think that a molecule with such weak intermolecular attractions as SF6 would form long chains of S atoms. Indeed, in standard conditions, SF6 is a gas.
Every electron carries one elementary negative charge. Concerning mass,
it takes roughly 1,840 electrons to make enough mass for 1 proton or 1 neutron.
Electrons don't necessarily have to stay connected to an atom, but when they do,
they circle the nucleus.
So you should select (C): ==> Negative, ==> light, ==> circling the nucleus.
Answer:
532 moles of O atoms.
Explanation:
Given data:
Number of moles of oxygen atom present = ?
Number of molecules of N₂O₅= 6.41×10²⁵ molecules
Solution:
First of all we will calculate the number of moles of N₂O₅.
1 mole = 6.022×10²³ molecules
6.41×10²⁵ molecules × 1 mol /6.022×10²³ molecules
106.4 mol
Number of atoms of O:
1 mole of N₂O₅ contain 5 moles of O atoms.
106.4×5 = 532 mol
Answer:
[NaCH₃COO] = 2.26M
Explanation:
17% by mass is a sort of concentration. Gives the information about grams of solute in 100 g of solution. (In this case, 17 g of NaCH₃COO)
Let's determine the volume of solution, by density
Mass of solution / Volume of solution = Solution density
100 g / Volume of solution = 1.09 g/mL
100 g / 1.09 g/mL = 91.7 mL
17 grams of solute is contained in 91.7 mL
Molarity (M) = Mol of solute /L of solution
91.7 mL / 1000 = 0.0917L
17 g / 82 g/m = 0.207 moles
Molariy = 0.207 moles / 0.0917L → 2.26M