The red semicircle shown in the weather chart represents warm front.
Answer:
HNO3 + H2S = H2O + NO + S - Chemical Equation Balancer. Balanced Chemical Equation. 2 HNO 3 + 3 H 2 S → 4 H 2 O + 2 NO + 3 S. Reaction Information. Nitric Acid + Hydrogen Sulfide = Water + Nitric Oxide (radical) + Sulfur . Reactants.
Explanation:
<span>In thermodynamics, the internal energy of a thermodynamic system, or a body with well-defined boundaries, denoted by U, or sometimes E, is the total of the kinetic energy due to the motion of molecules (translational, rotational, vibrational) and the potential energy associated with the vibrational and electric energy of atoms within molecules or crystals. It includes the energy in all the chemical bonds, and the energy of the free, conduction electrons in metals.</span>
Answer:
True
Explanation:
It is true that every element in the periodic table follows the Aufbau's principle.
The principle states that "the sublevels with lower energies are filled up before those with higher energies".
- Sublevels do not fill up in numerical order.
- This is true when writing the electronic configuration of all atoms on the periodic table.
Answer:
- <em><u>Mendeleev produced the first orderly arrangement of known elements.</u></em>
- <em><u>Mendeleev used patterns to predict undiscovered elements.</u></em>
Explanation:
- <u>Mendeleev produced the first orderly arrangement of known elements and used patterns to predict the undiscovered elements.</u>
Those two statments are true.
For the time being there were some 62 known elements. Before Medeleev some schemes to order part of the elements were proposed, but Medeleev showed the relationship between the atomic mass and the properties of the elements (supports second choice). This arrangement is known as the periodic table.
More importantly, Mendeleev predicted correctly the existance and properties of unknown elements, which is his major contribution: he left blanket spaces which where gradually filled when new elements where discovered (this supports the fourth choice).
The first modern chemistry book was written by Antoine Lavoisier (this discards first option).
Mendeleev ordered the elements by increasing mass number (this discards third choice), which was corrected later by the scientist Henry Moseley, who ordered the elements by increasing atomic number (number of protons).
Isotopes were not known by Mendeleev times, so this discards the last option.
