4. A
because PbCl2 is an ionic compound and it's solid, so it's a substance.
It cannot be mixture, because it's a pure molecule.
5. D
despite that both substances are gases, colorless they are different molecules, so they should have different either chemical and physical properties
6. C
this substance made from W atoms and others are made from molecules
The <span>source of fuel that is most widely used today is Natural gas. The answer is letter C. The rest of the choices do not answer the question above,</span>
According to avogadro constant, the number of units in one mole of any substance contain 6.022 x10 ^23 atoms
therefore the number of o atoms in one mole of CuSO4 = 6.022 x 10 ^ 23
Answer:
The elements can be classified as metals, nonmetals, or metalloids. Metals are good conductors of heat and electricity, and are malleable (they can be ... and electricity, and are not malleable or ductile; many of the elemental nonmetals are ... under certain circumstances, several of them can be made to conduct electricity.
Hope this helps!
Explanation:
Answer: C
Explanation:
The one closest to the atomic center, there is a single 1s orbital that can hold 2 electrons. At the next energy level, there are four orbitals.