The black lines in the Sun's spectrum are caused by gases on, or above, the Sun's surface that absorb some of the emitted light.
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A thermoplastic is a polymer that becomes pliable or moldable above a specific temperature and returns to a solid state upon cooling. These are the linear or slightly branched long chain molecules. For examples, PVC, polystyrene, nylon,polyethylene etc.
Explanation:
Answer:
Rutherford's theory laid the foundation upon which Bohr's model is founded. Rutherford established the fact that at the center of the atom, there is a nucleus whose radius is smaller than the radius of the atom. This nucleus is positively charged and most of the mass of the atom is concentrated there. Electrons move round this nucleus in orbits.
The experimental evidences of the Bohr's model shows that Rutherford's model was fundamentally correct. However, Bohr's model introduced the idea of quantization of the energy of electrons in an atom. The model went further to explain the spectra lines of the hydrogen atom.
Explanation:
Answer:
Answer is in the explanation.
Explanation:
For the reaction:
Ba₃(PO₄)₂(aq) + 3Na₂SO₄(aq) → 3BaSO₄(s) + 2Na₃PO₄(aq)
As Na₂SO₄(aq) is in excess, limiting reactant is Ba₃(PO₄)₂(aq). As the molarity of the solution is 0,25M and you knew the volume of the solution, you can obtain the moles of Ba₃(PO₄)₂ doing 0,25M×volume.
As 1 mol of Ba₃(PO₄)₂(aq) react with 3 moles of BaSO₄ the moles of BaSO₄ are three times moles of Ba₃(PO₄)₂.
As BaSO₄ molar mass is 233,38g/mol. The mass of BaSO₄ is given by moles of BaSO₄ × 233,38g/mol
I hope it helps!
